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Sample records for repetitive extragenic palindromic-pcr

  1. An investigation of the subtype diversity of clinical isolates of Irish Clostridium difficile ribotypes 027 and 078 by repetitive-extragenic palindromic PCR.

    LENUS (Irish Health Repository)

    Solomon, K

    2011-08-01

    A repetitive-extragenic palindromic PCR (rep-PCR) subtyping method (DiversiLab) in conjunction with ribotyping, toxinotyping and antimicrobial-susceptibility testing was used to detect subtypes within Clostridium difficile ribotypes 027 and 078. Clinical isolates of ribotypes 027 (toxinotype III) (n = 30) and 078 (toxinotype V) (n = 23) were provided by health-care facilities across the Republic of Ireland over 2 months in 2006 and 1 month in 2009. Ribotype 027 isolates were significantly more related to each other (9 different subtype profiles) when compared to ribotype 078 isolates (14 different profiles) (P = 0.001; cut-off >90 % similarity). Almost half of ribotype 078 isolates (45.5 %) showed no relationship to each other. The clonality of ribotype 027 isolates suggests effective adaptation to the human niche, whereas the considerable genetic diversity within ribotype 078 isolates suggests that they may have originated from a variety of sources. Subtyping correlated well with antimicrobial susceptibility, in particular clindamycin susceptibility for ribotype 027, but diverse antimicrobial-susceptibility profiles were seen in ribotype 078 isolates, even within a single health-care facility. Between 2006 and 2009, a change in the predominant subtype of ribotype 027 was seen, with the recent clone representing half of all ribotype 027 isolates studied. This strain exhibited 89 % similarity to a rep-PCR profile of the North American NAP-1 strain.

  2. Bacterial repetitive extragenic palindromic sequences are DNA targets for Insertion Sequence elements

    Directory of Open Access Journals (Sweden)

    Pareja Eduardo

    2006-03-01

    Full Text Available Abstract Background Mobile elements are involved in genomic rearrangements and virulence acquisition, and hence, are important elements in bacterial genome evolution. The insertion of some specific Insertion Sequences had been associated with repetitive extragenic palindromic (REP elements. Considering that there are a sufficient number of available genomes with described REPs, and exploiting the advantage of the traceability of transposition events in genomes, we decided to exhaustively analyze the relationship between REP sequences and mobile elements. Results This global multigenome study highlights the importance of repetitive extragenic palindromic elements as target sequences for transposases. The study is based on the analysis of the DNA regions surrounding the 981 instances of Insertion Sequence elements with respect to the positioning of REP sequences in the 19 available annotated microbial genomes corresponding to species of bacteria with reported REP sequences. This analysis has allowed the detection of the specific insertion into REP sequences for ISPsy8 in Pseudomonas syringae DC3000, ISPa11 in P. aeruginosa PA01, ISPpu9 and ISPpu10 in P. putida KT2440, and ISRm22 and ISRm19 in Sinorhizobium meliloti 1021 genome. Preference for insertion in extragenic spaces with REP sequences has also been detected for ISPsy7 in P. syringae DC3000, ISRm5 in S. meliloti and ISNm1106 in Neisseria meningitidis MC58 and Z2491 genomes. Probably, the association with REP elements that we have detected analyzing genomes is only the tip of the iceberg, and this association could be even more frequent in natural isolates. Conclusion Our findings characterize REP elements as hot spots for transposition and reinforce the relationship between REP sequences and genomic plasticity mediated by mobile elements. In addition, this study defines a subset of REP-recognizer transposases with high target selectivity that can be useful in the development of new tools for

  3. Antigenic variation by Borrelia hermsii occurs through recombination between extragenic repetitive elements on linear plasmids.

    Science.gov (United States)

    Dai, Qiyuan; Restrepo, Blanca I; Porcella, Stephen F; Raffel, Sandra J; Schwan, Tom G; Barbour, Alan G

    2006-06-01

    The relapsing fever agent Borrelia hermsii undergoes multiphasic antigenic variation through gene conversion of a unique expression site on a linear plasmid by an archived variable antigen gene. To further characterize this mechanism we assessed the repertoire and organization of archived variable antigen genes by sequencing approximately 85% of plasmids bearing these genes. Most archived genes shared with the expressed gene a UHS), that surrounded the start codon. The 59 archived variable antigen genes were arrayed in clusters with 13 repetitive, 214 nt long downstream homology sequence (DHS) elements distributed among them. A fourteenth DHS element was downstream of the expression locus. Informative nucleotide polymorphisms in UHS regions and DHS elements were applied to the analysis of the expression site of relapse serotypes from 60 infected mice in a prospective study. For most recombinations, the upstream crossover occurred in the UHS's second half, and the downstream crossover was in the DHS's second half. Usually the closest archival DHS element was used, but occasionally a more distant DHS was employed. The downstream extragenic crossover site in B. hermsii contrasts with the upstream [corrected] extragenic crossover site for antigenic variation in African trypanosomes.

  4. Cutting edge: natural DNA repetitive extragenic sequences from gram-negative pathogens strongly stimulate TLR9.

    Science.gov (United States)

    Magnusson, Mattias; Tobes, Raquel; Sancho, Jaime; Pareja, Eduardo

    2007-07-01

    Bacterial DNA exerts immunostimulatory effects on mammalian cells via the intracellular TLR9. Although broad analysis of TLR9-mediated immunostimulatory potential of synthetic oligonucleotides has been developed, which kinds of natural bacterial DNA sequences are responsible for immunostimulation are not known. This work provides evidence that the natural DNA sequences named repetitive extragenic palindromic (REPs) sequences present in Gram-negative bacteria are able to produce innate immune system stimulation via TLR9. A strong induction of IFN-alpha production by REPs from Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa, and Neisseria meningitidis was detected in splenocytes from 129 mice. In addition, the involvement of TLR9 in immune stimulation by REPs was confirmed using B6.129P2-Tlr9(tm1Aki) knockout mice. Considering the involvement of TLRs in Gram-negative septic shock, it is conceivable that REPs play a role in its pathogenesis. This study highlights REPs as a potential novel target in septic shock treatment.

  5. Genomic fingerprinting Acinetobacter baumannii: amplification of multiple inter-repetitive extragenic palindromic sequences.

    Science.gov (United States)

    Sheehan, C; Lynch, M; Cullen, C; Cryan, B; Greer, P; Fanning, S

    1995-09-01

    Acinetobacter species are important nosocomial pathogens. A rapid and sensitive identification system, capable of providing strain identity at the genetic level, is required to identify outbreak strains and facilitate the early implementation of infection control procedures. Repetitive extragenic palindromic (REP) elements, have been identified in numerous bacteria and these genomic sequences provide useful targets for DNA amplification. A method for amplifying inter-REP DNA sequences, REP-multiple arbitrary amplicon profiling (REP-MAAP), is described and applied to 29 Acinetobacter baumannii from clinical samples. Amplified polymorphic DNA patterns were demonstrated for all isolates and those displaying identical REP-MAAP patterns were considered identical at the genetic level. In the spring of 1993, 10 intensive care unit patients had endotracheal colonization with A. baumannii (five with REP-MAAP I and five with REP-MAAP II patterns). These findings suggested nosocomial transmission of organisms which was terminated by standard infection control measures. No further A. baumannii were detected until the winter of 1993 when isolates of different REP-MAAP groups emerged, suggesting that factors other than nosocomial transmission were implicated.

  6. Variation in extragenic repetitive DNA sequences in Pseudomonas syringae and potential use of modified REP primers in the identification of closely related isolates

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    Elif Çepni

    2012-01-01

    Full Text Available In this study, Pseudomonas syringe pathovars isolated from olive, tomato and bean were identified by species-specific PCR and their genetic diversity was assessed by repetitive extragenic palindromic (REP-PCR. Reverse universal primers for REP-PCR were designed by using the bases of A, T, G or C at the positions of 1, 4 and 11 to identify additional polymorphism in the banding patterns. Binding of the primers to different annealing sites in the genome revealed additional fingerprint patterns in eight isolates of P. savastanoi pv. savastanoi and two isolates of P. syringae pv. tomato. The use of four different bases in the primer sequences did not affect the PCR reproducibility and was very efficient in revealing intra-pathovar diversity, particularly in P. savastanoi pv. savastanoi. At the pathovar level, the primer BOX1AR yielded shared fragments, in addition to five bands that discriminated among the pathovars P. syringae pv. phaseolicola, P. savastanoi pv. savastanoi and P. syringae pv. tomato. REP-PCR with a modified primer containing C produced identical bands among the isolates in a pathovar but separated three pathovars more distinctly than four other primers. Although REP-and BOX-PCRs have been successfully used in the molecular identification of Pseudomonas isolates from Turkish flora, a PCR based on inter-enterobacterial repetitive intergenic concensus (ERIC sequences failed to produce clear banding patterns in this study.

  7. Indole acetic acid production by fluorescent Pseudomonas spp. from the rhizosphere of Plectranthus amboinicus (Lour.) Spreng. and their variation in extragenic repetitive DNA sequences.

    Science.gov (United States)

    Sethia, Bedhya; Mustafa, Mariam; Manohar, Sneha; Patil, Savita V; Jayamohan, Nellickal Subramanian; Kumudini, Belur Satyan

    2015-06-01

    Fluorescent Pseudomonas (FP) is a heterogenous group of growth promoting rhizobacteria that regulate plant growth by releasing secondary metabolic compounds viz., indole acetic acid (IAA), siderophores, ammonia and hydrogen cyanide. In the present study, IAA producing FPs from the rhizosphere of Plectranthus amboinicus were characterized morphologically, biochemically and at the molecular level. Molecular identification of the isolates were carried out using Pseudomonas specific primers. The effect of varying time (24, 48, 72 and 96 h), Trp concentrations (100, 200, 300, 400 and 500 μg x ml(-1)), temperature (10, 26, 37 and 50 ± 2 degrees C) and pH (6, 7 and 8) on IAA production by 10 best isolates were studied. Results showed higher IAA production at 72 h incubation, at 300 μg x ml(-1) Trp concentration, temperature 26 ± 2 degrees C and pH 7. TLC with acidified ethyl acetate extract showed that the IAA produced has a similar Rf value to that of the standard IAA. Results of TLC were confirmed by HPLC analysis. Genetic diversity of the isolates was also studied using 40 RAPD and 4 Rep primers. Genetic diversity parameters such as dominance, Shannon index and Simpson index were calculated. Out of 40 RAPD primers tested, 9 (2 OP-D series and 7 OP-E series) were shortlisted for further analysis. Studies using RAPD, ERIC, BOX, REP and GTG5 primers revealed that isolates exhibit significant diversity in repetitive DNA sequences irrespective of the rhizosphere.

  8. Screening and detection of repetitive extragenic palindromic sequences with TLR9 agonistic activity from Brucella abortus DNA%活化TLR9的牛种布氏菌基因外重复回文序列筛选及活性检测

    Institute of Scientific and Technical Information of China (English)

    张雅娴; 白丽云; 王占黎; 王英; 于慧

    2016-01-01

    目的 筛选具有活化Toll样受体9(TLR9)的牛种布氏菌基因外重复回文序列(Repetitive Extragenic Palin-drome Squence,REPs)并检测其活性,为布氏菌病的治疗提供新思路.方法 基于Brucella abortus A13334基因组序列,利用生物信息学技术识别其REPs后,合成序列.将合成的天然骨架的脱氧寡核苷酸(ODNs)转染小鼠单核巨噬细胞株RAW264.7,以ELISA检测IFN-α的分泌水平.采用TLR9-siRNA沉默RAW264.7中的TLR9,将上述诱导IFN-α分泌增加的阳性ODN序列转染RAW264.7,ELISA方法检测IFN-α的分泌变化.结果 筛选出1857条牛种布氏菌REPs,选择2级茎环结构较好的5条ODNs序列进行合成,ELISA方法检测显示ODNs M4、M5介导IFN-α分泌量显著高于阴性对照(P<0.05),且阳性ODN M5所介导的IFN-α分泌可以被TLR9-siRNA显著抑制.结论 布氏菌基因组中存在可以活化TLR9信号通路的REPs,此结果有助于对布氏菌致病和免疫机制的认识.

  9. 羊种布氏杆菌基因外重复回文序列经Toll样受体9诱导IFN-α表达的研究%The effects of repetitive extragenic palindromic sequences from Brucella melitensis DNA on the toll-like receptor 9-mediated interferon-α production

    Institute of Scientific and Technical Information of China (English)

    白丽云; 张雅娴; 王占黎; 王英; 于慧

    2015-01-01

    Objective To screen the repetitive extragenic palindromic sequences with activation of toll-like receptor 9(TLR9) activity from Brucella melitensis DNA,providing new ideas and new targets for prevention and treatment of brucellosis.Methods Bioinformatics methods were used to detect repetitive extragenic palindromic(REP) sequences from Brucella melitensis DNA.The studied REPs were selected and synthesized.RAW264.7 was cultured and transfected with REPs mediated by lipofectamine 3000.Additionally,TLR9-siRNA was used to downregulate TLR9 expression.The content of interferon-α(IFN-α) in the supernatant was then measured by ELISA.Results A total of 2 200 REP sequences in Brucella melitensis DNA were identified.Twelve REP sequences were synthesized for further detecting of the TLR9 agonistic activity.IFN-α expression in RAW264.7 treated with M2,M3,M4,M5,M6,M7,M9,M12 were (26.944 ± 1.868),(46.461 ± 2.562),(34.980 ± 2.055),(43.016 ± 2.162),(62.533 ± 4.031),(67.125 ± 5.069),(18.908 ± 1.633),(39.572 ± 2.465) pg/ml respectively,which significantly increased when compared with the negative control group [(12.594 ± 1.338) pg/ml,t =10.817,20.295,15.812,20.724,20.365,18.016,5.180,16.660,all P < 0.05].Additionally,TLR9-siRNA can significantly decrease the levels of IFN-α in RAW264.7 treated with M6.Conclusion REP sequences presented in Brucella melitensis DNA are able to induce IFN-α expression through TLR9,which can be helpful for the understanding of pathogenesis and immunity of Brucella melitensis.%目的 筛选具有活化Toll样受体9(TLR9)活性的羊种布氏杆菌DNA中基因外重复回文序列(REPs),检测其经TLR9诱导的干扰素-α(IFN-α)表达,为羊种布氏杆菌病的防治提供新思路.方法 针对羊种布氏杆菌Brucella melitensis NI基因组序列,利用生物信息学技术识别其REPs后,合成序列.将合成的天然骨架脱氧寡核苷酸(ODNs)转染小鼠单核巨噬细胞株RAW264.7,酶联免疫吸附测定法(ELISA)检测IFN

  10. Genetic relatedness among tdh+ and trh+ Vibrio parahaemolyticus cultured from Gulf of Mexico oysters (Crassostrea virginica) and surrounding water and sediment.

    Science.gov (United States)

    Johnson, C N; Flowers, A R; Young, V C; Gonzalez-Escalona, N; DePaola, A; Noriea, N F; Grimes, D J

    2009-04-01

    Pathogenic Vibrio parahaemolyticus (Vp) (tdh(+)/trh(+)) represent a small percentage of environmental Vp populations, and very little is known about this subpopulation. Repetitive extragenic palindromic PCR and multilocus sequence analysis revealed heterogeneity among 41 Vp containing thermostable direct hemolysin (tdh) and tdh-related hemolysin (trh) that were isolated from Mississippi coastal environments from October 2006 to April 2007. There was no source-specific sequestering in oysters, water, or sediment.

  11. Multi-Locus Sequence Typing (MLST) and Repetitive Extragenic Palindromic Polymerase Chain Reaction (REP-PCR), characterization of shigella spp. over two decades in Tianjin China

    Science.gov (United States)

    Cao, Yang; Wei, Dianjun; kamara, Idrissa L; Chen, Wei

    2012-01-01

    To understand the change of the dominant serogroup of Shigella spp., their antimicrobial resistance over more than two decades in Tianjin, their phylogenetic similarity and to determine their evolutionary biology by using REP-PCR and MLST in order to study their epidemiological character. Multi-locus Sequence Typing was performed to determine their lineage and phylogenetic similarity. REP-PCR typing was used to study the homology of their genomic DNA. The isolated rate of group D Shigella in 2009 and 2010 had obviously increased. Antimicrobial susceptibility test results showed that the resistant rates of the 1981-1983 Shigella flexneri to tetracycline, streptomycin and chloramphenicol varied from 76.47 to 100%, they were all sensitive to other antibiotics. During 2009-2010, the resistance rates of the isolated Shigella flexneri to gentamicin, amikacin, third and fourth Generation Cephalosporins and quinolones had increased. MLST results produced five sequence types and two sequence type complexes. REP-PCR showed DNA band similarities between the 1981-1983 and 2009-2010 strains. The dominant serogroup of Shigella in Tianjin has changed from Shigella flexneri to Shigella sonnei. Increased drug resistance of Shigella flexneri is higher than Shigella sonnei because a great variety of antibiotics has been used. The MLST results showed that the 1981-1983 strains had the same sequence type with some of the 2009-2010 strains. Combination of MLST and REP-PCR produced better discriminatory power than using either method alone. PMID:23205184

  12. Repetitive maladaptive behavior: beyond repetition compulsion.

    Science.gov (United States)

    Bowins, Brad

    2010-09-01

    Maladaptive behavior that repeats, typically known as repetition compulsion, is one of the primary reasons that people seek psychotherapy. However, even with psychotherapeutic advances it continues to be extremely difficult to treat. Despite wishes and efforts to the contrary repetition compulsion does not actually achieve mastery, as evidenced by the problem rarely resolving without therapeutic intervention, and the difficulty involved in producing treatment gains. A new framework is proposed, whereby such behavior is divided into behavior of non-traumatic origin and traumatic origin with some overlap occurring. Repetitive maladaptive behavior of non-traumatic origin arises from an evolutionary-based process whereby patterns of behavior frequently displayed by caregivers and compatible with a child's temperament are acquired and repeated. It has a familiarity and ego-syntonic aspect that strongly motivates the person to retain the behavior. Repetitive maladaptive behavior of traumatic origin is characterized by defensive dissociation of the cognitive and emotional components of trauma, making it very difficult for the person to integrate the experience. The strong resistance of repetitive maladaptive behavior to change is based on the influence of both types on personality, and also factors specific to each. Psychotherapy, although very challenging at the best of times, can achieve the mastery wished and strived for, with the aid of several suggestions provided.

  13. Genetic relatedness of commensal Escherichia coli from nursery pigs in intensive pig production in Denmark and molecular characterization of genetically different strains

    DEFF Research Database (Denmark)

    Herrero Fresno, Ana; Larsen, Inge; Olsen, John Elmerdahl

    2015-01-01

    AIMS: To determine the genetic relatedness and the presence of virulence and antibiotic resistance genes in commensal Escherichia coli from nursery pigs in Danish intensive production. METHODS AND RESULTS: The genetic diversity of 1000 E. coli strains randomly picked (N = 50 isolates) from cultured...... faecal samples (N = 4 pigs) from five intensive Danish pigs farms was analysed by repetitive extragenic palindromic-PCR (REP-PCR) and 42 unique REP-profiles were detected (similarity commensal E. coli......-producing genes were observed in 20 isolates. CONCLUSIONS: A low genetic diversity was found in commensal gut E. coli from nursery pigs in Denmark. No correlation was observed between REP-profiles, ST-types and resistance/virulence patterns. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study analysing...

  14. Does Virulence Assessment of Vibrio anguillarum Using Sea Bass (Dicentrarchus labrax) Larvae Correspond with Genotypic and Phenotypic Characterization?

    DEFF Research Database (Denmark)

    Frans, Ingeborg; Dierckens, Kristof; Crauwels, Sam

    2013-01-01

    hosts. In addition, to assess potential relationships between virulence and genotypic and phenotypic characteristics, the strains were characterized by random amplified polymorphic DNA (RAPD) and repetitive extragenic palindromic PCR (rep-PCR) analyses, as well as by phenotypic analyses using Biolog......'s Phenotype MicroArray (TM) technology and some virulence factor assays. Conclusions/Significance: Virulence testing revealed ten virulent and five avirulent strains. While some relation could be established between serotype, genotype and phenotype, no relation was found between virulence and genotypic...... or phenotypic characteristics, illustrating the complexity of V. anguillarum virulence. Moreover, the standardized gnotobiotic system used in this study has proven its strength as a model to assess and compare the virulence of different V. anguillarum strains in vivo. In this way, the bioassay contributes...

  15. Grammatical Change through Repetition.

    Science.gov (United States)

    Arevart, Supot

    1989-01-01

    The effect of repetition on grammatical change in an unrehearsed talk is examined based on a case study of a single learner. It was found that repetition allows for accuracy monitoring in that errors committed in repeated contexts undergo correction. Implications for teaching are discussed. (23 references) (LB)

  16. The Negative Repetition Effect

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    Mulligan, Neil W.; Peterson, Daniel J.

    2013-01-01

    A fundamental property of human memory is that repetition enhances memory. Peterson and Mulligan (2012) recently documented a surprising "negative repetition effect," in which participants who studied a list of cue-target pairs twice recalled fewer targets than a group who studied the pairs only once. Words within a pair rhymed, and…

  17. Class 1 integrons in non-clonal multidrug-resistant Acinetobacter baumannii from Iran, description of the new blaIMP-55 allele in In1243.

    Science.gov (United States)

    Azizi, Omid; Shakibaie, Mohammad Reza; Badmasti, Farzad; Modarresi, Farzan; Ramazanzadeh, Rashid; Mansouri, Shahla; Shahcheraghi, Fereshteh

    2016-09-01

    Infections and outbreaks caused by multidrug-resistant Acinetobacter baumannii (MDR-AB) are prevalent and have been reported worldwide over the past 20 or more years. Class 1 integron in MDR-AB plays an important role in the spread of antibiotic resistance in clinical settings. This study has been conducted to evaluate the detection of metallo-β-lactamase, characterization of class 1 integron and determination of clonal relatedness among A. baumannii hospital isolates. Sixty-five clinical isolates of MDR-AB were recovered from two Iranian hospital's intensive care units from February to August 2013. Integrase (intI1) and blaIMP genes were detected in 70.8 % (n=46/65) and 9.23 % (n=6/65) of the isolates using PCR assay, respectively. No other metallo-β-lactamase genes (blaVIM, blaSIM and blaNDM) were detected. PCR sequencing of integron gene cassette revealed the following arrays: blaOXA10-aacA4-blaIMP-55-cmlA5 (as a novel array was designated In1243), aacC1 and aadA1. Analysis of blaIMP gene revealed a new allele designated as blaIMP-55. Gene transfer experiment by conjugation showed the 36 kb conjugative plasmid harbouring In1243. The clonal assessment by repetitive extragenic palindromic PCR demonstrated a high-degree relatedness among the strains, but strains harbouring In1243 displayed a different repetitive extragenic palindromic PCR profile. In this study, we found that a novel class 1 integron (In1243) that encoded a new blaIMP allele resided on a transferable plasmid in non-clonal strains of MDR-AB.

  18. Roles of repetitive sequences

    Energy Technology Data Exchange (ETDEWEB)

    Bell, G.I.

    1991-12-31

    The DNA of higher eukaryotes contains many repetitive sequences. The study of repetitive sequences is important, not only because many have important biological function, but also because they provide information on genome organization, evolution and dynamics. In this paper, I will first discuss some generic effects that repetitive sequences will have upon genome dynamics and evolution. In particular, it will be shown that repetitive sequences foster recombination among, and turnover of, the elements of a genome. I will then consider some examples of repetitive sequences, notably minisatellite sequences and telomere sequences as examples of tandem repeats, without and with respectively known function, and Alu sequences as an example of interspersed repeats. Some other examples will also be considered in less detail.

  19. Roles of repetitive sequences

    Energy Technology Data Exchange (ETDEWEB)

    Bell, G.I.

    1991-12-31

    The DNA of higher eukaryotes contains many repetitive sequences. The study of repetitive sequences is important, not only because many have important biological function, but also because they provide information on genome organization, evolution and dynamics. In this paper, I will first discuss some generic effects that repetitive sequences will have upon genome dynamics and evolution. In particular, it will be shown that repetitive sequences foster recombination among, and turnover of, the elements of a genome. I will then consider some examples of repetitive sequences, notably minisatellite sequences and telomere sequences as examples of tandem repeats, without and with respectively known function, and Alu sequences as an example of interspersed repeats. Some other examples will also be considered in less detail.

  20. Repetition and Translation Shifts

    Directory of Open Access Journals (Sweden)

    Simon Zupan

    2006-06-01

    Full Text Available Repetition manifests itself in different ways and at different levels of the text. The first basic type of repetition involves complete recurrences; in which a particular textual feature repeats in its entirety. The second type involves partial recurrences; in which the second repetition of the same textual feature includes certain modifications to the first occurrence. In the article; repetitive patterns in Edgar Allan Poe’s short story “The Fall of the House of Usher” and its Slovene translation; “Konec Usherjeve hiše”; are compared. The author examines different kinds of repetitive patterns. Repetitions are compared at both the micro- and macrostructural levels. As detailed analyses have shown; considerable microstructural translation shifts occur in certain types of repetitive patterns. Since these are not only occasional; sporadic phenomena; but are of a relatively high frequency; they reduce the translated text’s potential for achieving some of the gothic effects. The macrostructural textual property particularly affected by these shifts is the narrator’s experience as described by the narrative; which suffers a reduction in intensity.

  1. Trialogue: Preparation, Repetition and...

    Science.gov (United States)

    Oberg, Antoinette; And Others

    1996-01-01

    This paper interrogates both curriculum theory and the limits and potentials of textual forms. A set of overlapping discourses (a trialogue) focuses on inquiring into the roles of obsession and repetition in creating deeply interpretive locations for understanding. (SM)

  2. Novel porcine repetitive elements

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    Nonneman Dan J

    2006-12-01

    Full Text Available Abstract Background Repetitive elements comprise ~45% of mammalian genomes and are increasingly known to impact genomic function by contributing to the genomic architecture, by direct regulation of gene expression and by affecting genomic size, diversity and evolution. The ubiquity and increasingly understood importance of repetitive elements contribute to the need to identify and annotate them. We set out to identify previously uncharacterized repetitive DNA in the porcine genome. Once found, we characterized the prevalence of these repeats in other mammals. Results We discovered 27 repetitive elements in 220 BACs covering 1% of the porcine genome (Comparative Vertebrate Sequencing Initiative; CVSI. These repeats varied in length from 55 to 1059 nucleotides. To estimate copy numbers, we went to an independent source of data, the BAC-end sequences (Wellcome Trust Sanger Institute, covering approximately 15% of the porcine genome. Copy numbers in BAC-ends were less than one hundred for 6 repeat elements, between 100 and 1000 for 16 and between 1,000 and 10,000 for 5. Several of the repeat elements were found in the bovine genome and we have identified two with orthologous sites, indicating that these elements were present in their common ancestor. None of the repeat elements were found in primate, rodent or dog genomes. We were unable to identify any of the replication machinery common to active transposable elements in these newly identified repeats. Conclusion The presence of both orthologous and non-orthologous sites indicates that some sites existed prior to speciation and some were generated later. The identification of low to moderate copy number repetitive DNA that is specific to artiodactyls will be critical in the assembly of livestock genomes and studies of comparative genomics.

  3. MIMICRY, DIFFERENCE AND REPETITION

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    Marcelo Mendes de Souza

    2008-07-01

    Full Text Available This article addresses Homi K. Bhabha’s concept of mimicry in a broader context, other than that of cultural studies and post-colonial studies, bringing together other concepts, such as that of Gilles Deleuze in Difference and repetition, among other texts, and other names, such as Silviano Santiago, Jorge Luís Borges, Franz Kafka and Giorgio Agamben. As a partial conclusion, the article intends to oppose Bhabha’s freudian-marxist view to Five propositions on Psychoanalysis (1973, Gilles Deleuze’s text about Psychoanalysis published right after his book The Anti-Oedipus.

  4. Repetition in Waiting for Godot

    Institute of Scientific and Technical Information of China (English)

    李想; 魏妍

    2015-01-01

    Waiting for Godot is one of the most famous plays written by Samuel Barclay Beckett, and also is the founding work of“Theatre of the Absurd”. In the drama, repetitive phenomena shed light on the whole construction considerably. All the charac-ters were helpless and unthinking. Their dialogues were simple, nonsense and repetitive. Two scenes were cyclical. Repetition was used subtly in order to express the theme of the play, showing mental crisis after depravation of WWII.

  5. Understanding maximal repetitions in strings

    CERN Document Server

    Crochemore, Maxime

    2008-01-01

    The cornerstone of any algorithm computing all repetitions in a string of length n in O(n) time is the fact that the number of runs (or maximal repetitions) is O(n). We give a simple proof of this result. As a consequence of our approach, the stronger result concerning the linearity of the sum of exponents of all runs follows easily.

  6. Perceptual Repetition Blindness Effects

    Science.gov (United States)

    Hochhaus, Larry; Johnston, James C.; Null, Cynthia H. (Technical Monitor)

    1994-01-01

    The phenomenon of repetition blindness (RB) may reveal a new limitation on human perceptual processing. Recently, however, researchers have attributed RB to post-perceptual processes such as memory retrieval and/or reporting biases. The standard rapid serial visual presentation (RSVP) paradigm used in most RB studies is, indeed, open to such objections. Here we investigate RB using a "single-frame" paradigm introduced by Johnston and Hale (1984) in which memory demands are minimal. Subjects made only a single judgement about whether one masked target word was the same or different than a post-target probe. Confidence ratings permitted use of signal detection methods to assess sensitivity and bias effects. In the critical condition for RB a precue of the post-target word was provided prior to the target stimulus (identity precue), so that the required judgement amounted to whether the target did or did not repeat the precue word. In control treatments, the precue was either an unrelated word or a dummy.

  7. Repetition in English Political Public Speaking

    Institute of Scientific and Technical Information of China (English)

    李红梅

    2010-01-01

    Repetition is frequently used in English political public speaking to make it easy to be remembered and powerful to move the feelings of the public. This paper is intended to analyze the functions of repetition and different levels of repetition to highlight the significance of repetition in English political public speaking and the ability of using it in practice.

  8. Varianish: Jamming with Pattern Repetition

    Directory of Open Access Journals (Sweden)

    Jort Band

    2014-10-01

    Full Text Available In music, patterns and pattern repetition are often regarded as a machine-like task, indeed often delegated to drum Machines and sequencers. Nevertheless, human players add subtle differences and variations to repeated patterns that are musically interesting and often unique. Especially when looking at minimal music, pattern repetitions create hypnotic effects and the human mind blends out the actual pattern to focus on variation and tiny differences over time. Varianish is a musical instrument that aims at turning this phenomenon into a new musical experience for musician and audience: Musical pattern repetitions are found in live music and Varianish generates additional (musical output accordingly that adds substantially to the overall musical expression. Apart from the theory behind the pattern finding and matching and the conceptual design, a demonstrator implementation of Varianish is presented and evaluated.

  9. REPETITIVE CLUSTER-TILTED ALGEBRAS

    Institute of Scientific and Technical Information of China (English)

    Zhang Shunhua; Zhang Yuehui

    2012-01-01

    Let H be a finite-dimensional hereditary algebra over an algebraically closed field k and CFm be the repetitive cluster category of H with m ≥ 1.We investigate the properties of cluster tilting objects in CFm and the structure of repetitive clustertilted algebras.Moreover,we generalize Theorem 4.2 in [12](Buan A,Marsh R,Reiten I.Cluster-tilted algebra,Trans.Amer.Math.Soc.,359(1)(2007),323-332.) to the situation of CFm,and prove that the tilting graph KCFm of CFm is connected.

  10. Repetitive elements in parasitic protozoa

    Directory of Open Access Journals (Sweden)

    Clayton Christine

    2010-05-01

    Full Text Available Abstract A recent paper published in BMC Genomics suggests that retrotransposition may be active in the human gut parasite Entamoeba histolytica. This adds to our knowledge of the various types of repetitive elements in parasitic protists and the potential influence of such elements on pathogenicity. See research article http://www.biomedcentral.com/1471-2164/11/321

  11. Repetition suppression and repetition priming are processing outcomes.

    Science.gov (United States)

    Wig, Gagan S

    2012-01-01

    Abstract There is considerable evidence that repetition suppression (RS) is a cortical signature of previous exposure to the environment. In many instances RS in specific brain regions is accompanied by improvements in specific behavioral measures; both observations are outcomes of repeated processing. In understanding the mechanism by which brain changes give rise to behavioral changes, it is important to consider what aspect of the environment a given brain area or set of areas processes, and how this might be expressed behaviorally.

  12. Cohesive Function of Lexical Repetition in Text

    Institute of Scientific and Technical Information of China (English)

    张莉; 卢沛沛

    2013-01-01

    Lexical repetition is the most direct form of lexical cohesion,which is the central device for making texts hang together. Although repetition is the most direct way to emphasize,it performs the cohesive effect more apparently.

  13. Circuit considerations for repetitive railguns

    Energy Technology Data Exchange (ETDEWEB)

    Honih, E.M.

    1986-01-01

    Railgun electromagnetic launchers have significant military and scientific potential. They provide direct conversion of electrical energy to projectile kinetic energy, and they offer the hope of achieving projectile velocities greatly exceeding the limits of conventional guns. With over 10 km/sec already demonstrated, railguns are attracting attention for tactical and strategic weapons systems and for scientific equation-of-state research. The full utilization of railguns will require significant improvements in every aspect of system design - projectile, barrel, and power source - to achieve operation on a large scale. This paper will review fundamental aspects of railguns, with emphasis on circuit considerations and repetitive operation.

  14. A BOX-SCAR fragment for the identification of Actinobacillus pleuropneumoniae.

    Science.gov (United States)

    Rossi, Ciro C; Pereira, Monalessa F; Langford, Paul R; Bazzolli, Denise M S

    2014-03-01

    Bacterial respiratory diseases are responsible for considerable mortality, morbidity and economic losses in the swine industry. Actinobacillus pleuropneumoniae, the causative agent of porcine pleuropneumonia, is one of the most important disease agents, but its identification and surveillance can be impaired by the existence of many other related bacteria in normal swine microbiota. In this work, we have evaluated a BOX-A1R-based repetitive extragenic palindromic-PCR (BOX-PCR) sequence characterised amplified region (SCAR) marker for the specific identification of A. pleuropneumoniae and its use in a multiplex PCR to detect additionally Haemophilus parasuis and Pasteurella multocida, two other major respiratory pathogens of pigs that are members of the family Pasteurellaceae. PCRs based on the BOX-SCAR fragment developed were rapid, sensitive and differentiated A. pleuropneumoniae from all swine-related members of the Pasteurellaceae family tested. Single and multiplex BOX-SCAR fragment-based PCRs can be used to identify A. pleuropneumoniae from other bacterial swine pathogens and will be useful in surveillance and epidemiological studies. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  15. Characterization of strains unlike Mesorhizobium loti that nodulate lotus spp. in saline soils of Granada, Spain.

    Science.gov (United States)

    Lorite, María J; Muñoz, Socorro; Olivares, José; Soto, María J; Sanjuán, Juan

    2010-06-01

    Lotus species are forage legumes with potential as pastures in low-fertility and environmentally constrained soils, owing to their high persistence and yield under those conditions. The aim of this work was the characterization of phenetic and genetic diversity of salt-tolerant bacteria able to establish efficient symbiosis with Lotus spp. A total of 180 isolates able to nodulate Lotus corniculatus and Lotus tenuis from two locations in Granada, Spain, were characterized. Molecular identification of the isolates was performed by repetitive extragenic palindromic PCR (REP-PCR) and 16S rRNA, atpD, and recA gene sequence analyses, showing the presence of bacteria related to different species of the genus Mesorhizobium: Mesorhizobium tarimense/Mesorhizobium tianshanense, Mesorhizobium chacoense/Mesorhizobium albiziae, and the recently described species, Mesorhizobium alhagi. No Mesorhizobium loti-like bacteria were found, although most isolates carried nodC and nifH symbiotic genes closely related to those of M. loti, considered the type species of bacteria nodulating Lotus, and other Lotus rhizobia. A significant portion of the isolates showed both high salt tolerance and good symbiotic performance with L. corniculatus, and many behaved like salt-dependent bacteria, showing faster growth and better symbiotic performance when media were supplemented with Na or Ca salts.

  16. Mutations in the lux operon of natural dark mutants in the genus Vibrio.

    Science.gov (United States)

    O'Grady, Elizabeth A; Wimpee, Charles F

    2008-01-01

    Bacterial bioluminescence can display a wide range of intensities among strains, from very bright to undetectable, and it has been shown previously that there are nonluminous vibrios that possess lux genes. In this paper, we report the isolation and characterization of completely dark natural mutants in the genus Vibrio. Screening of over 600 Vibrio isolates with a luxA gene probe revealed that approximately 5% carried the luxA gene. Bioluminescence assays of the luxA-positive isolates, followed by repetitive extragenic palindromic-PCR fingerprinting, showed three unique genotypes that are completely dark. The dark mutants show a variety of lesions, including an insertion sequence, point mutations, and deletions. Strain BCB451 has an IS10 insertion sequence in luxA, a mutated luxE stop codon, and a truncated luxH. Strain BCB494 has a 396-bp deletion in luxC, and strain BCB440 has a frameshift in luxC. This paper represents the first molecular characterization of natural dark mutants and the first demonstration of incomplete lux operons in natural isolates.

  17. Correlation Between ISAba1 Upstream ampC Gene and Resistance to Cefotaxime in Acinetobacter baumannii: A Serious Threat to Nosocomial Infections

    Directory of Open Access Journals (Sweden)

    Rezaee

    2016-01-01

    Full Text Available Background Infections due to Acinetobacter baumannii have become a significant challenge in modern healthcare systems. The global upsurge of multidrug resistance in A. baumannii has created widespread problems in the treatment of patients. Objectives We examined the prevalence ISAmpC and its correlation with cefotaxime resistance. Materials and Methods Standard biochemical tests were used to identify isolates. Genomic species of the genus Acinetobacter were confirmed by Amplified Ribosomal DNA Restriction Analysis (ARDRA. The susceptibility of 50 A. baumannii isolates to a variety of antimicrobial agents was determined using the disk diffusion method and E-test strips. PCR was used to investigate the connection of insertion sequences and the ampC gene. Clonal relatedness was determined by Repetitive Extragenic Palindromic PCR. Results ISAba1 located upstream of blaampC was found in 24 (48% of the A. baumannii isolates. In all of the studied isolates that had ISAmpC, the MIC for cefotaxime was 64 - 256 μg/mL. Based on the REP-PCR patterns among the resistant isolates, the highest number of ISAmpC positive isolates belonged to type B (n = 19 and type C (n = 12. Conclusions ISAba1 has become an important factor in A. baumannii’s resistance to cefotaxime.

  18. Does virulence assessment of Vibrio anguillarum using sea bass (Dicentrarchus labrax larvae correspond with genotypic and phenotypic characterization?

    Directory of Open Access Journals (Sweden)

    Ingeborg Frans

    Full Text Available BACKGROUND: Vibriosis is one of the most ubiquitous fish diseases caused by bacteria belonging to the genus Vibrio such as Vibrio (Listonella anguillarum. Despite a lot of research efforts, the virulence factors and mechanism of V. anguillarum are still insufficiently known, in part because of the lack of standardized virulence assays. METHODOLOGY/PRINCIPAL FINDINGS: We investigated and compared the virulence of 15 V. anguillarum strains obtained from different hosts or non-host niches using a standardized gnotobiotic bioassay with European sea bass (Dicentrarchus labrax L. larvae as model hosts. In addition, to assess potential relationships between virulence and genotypic and phenotypic characteristics, the strains were characterized by random amplified polymorphic DNA (RAPD and repetitive extragenic palindromic PCR (rep-PCR analyses, as well as by phenotypic analyses using Biolog's Phenotype MicroArray™ technology and some virulence factor assays. CONCLUSIONS/SIGNIFICANCE: Virulence testing revealed ten virulent and five avirulent strains. While some relation could be established between serotype, genotype and phenotype, no relation was found between virulence and genotypic or phenotypic characteristics, illustrating the complexity of V. anguillarum virulence. Moreover, the standardized gnotobiotic system used in this study has proven its strength as a model to assess and compare the virulence of different V. anguillarum strains in vivo. In this way, the bioassay contributes to the study of mechanisms underlying virulence in V. anguillarum.

  19. Characterization of tropical tree rhizobia and description of Mesorhizobium plurifarium sp. nov.

    Science.gov (United States)

    de Lajudie, P; Willems, A; Nick, G; Moreira, F; Molouba, F; Hoste, B; Torck, U; Neyra, M; Collins, M D; Lindström, K; Dreyfus, B; Gillis, M

    1998-04-01

    A collection of strains isolated from root nodules of Acacia species in Senegal was analysed previously by electrophoresis of total cell protein, auxanographic tests, rRNA-DNA hydridization, 16S rRNA gene sequencing, DNA base composition and DNA-DNA hybridization [de Lajudie, P., Willems, A., Pot, B. & 7 other authors (1994). Int J Syst Bacteriol 44, 715-733]. Strains from Acacia were shown to belong to two groups, Sinorhizobium terangae, and a so-called gel electrophoretic cluster U, which also included some reference strains from Brazil. Further taxonomic characterization of this group using the same techniques plus repetitive extragenic palindromic-PCR and nodulation tests is presented in this paper. Reference strains from Sudan and a number of new rhizobia isolated from nodules of Acacia senegal, Acacia tortilis subsp. raddiana and Prosopis juliflora in Senegal were included. As a result of this polyphasic approach, the creation of a new species, Mesorhizobium plurifarium, is proposed for a genotypically and phenotypically distinct group corresponding to the former cluster U and containing strains isolated from Acacia, Leucaena, Prosopis and Chamaecrista in West Africa (Senegal), East Africa (Sudan) and South America (Brazil). The type strain of Mesorhizobium plurifarium ORS 1032 has been deposited in the LMG collection as LMG 11892.

  20. Genetic Relatedness of Salmonella Serovars Isolated from Catfish (Clarias gariepinus) and Tilapia (Tilapia mossambica) Obtained from Wet Markets and Ponds in Penang, Malaysia.

    Science.gov (United States)

    Budiati, Titik; Rusul, Gulam; Wan-Abdullah, Wan Nadiah; Chuah, Li-Oon; Ahmad, Rosma; Thong, Kwai Lin

    2016-04-01

    A total of 43 Salmonella enterica isolates belonging to different serovars (Salmonella Albany, Salmonella Agona, Salmonella Corvallis, Salmonella Stanley, Salmonella Typhimurium, Salmonella Mikawasima, and Salmonella Bovismorbificans) were isolated from catfish (Clarias gariepinus) and tilapia (Tilapia mossambica) obtained from nine wet markets and eight ponds in Penang, Malaysia. Thirteen, 19, and 11 isolates were isolated from 9 of 32 catfish, 14 of 32 tilapia, and 11 of 44 water samples, respectively. Fish reared in ponds were fed chicken offal, spoiled eggs, and commercial fish feed. The genetic relatedness of these Salmonella isolates was determined by random amplified polymorphic DNA PCR (RAPD-PCR) using primer OPC2, repetitive extragenic palindromic PCR (REP-PCR), and pulsed-field gel electrophoresis (PFGE). Composite analysis of the RAPD-PCR, REP-PCR, and PFGE results showed that the Salmonella serovars could be differentiated into six clusters and 15 singletons. RAPD-PCR differentiated the Salmonella isolates into 11 clusters and 10 singletons, while REP-PCR differentiated them into 4 clusters and 1 singleton. PFGE differentiated the Salmonella isolates into seven clusters and seven singletons. The close genetic relationship of Salmonella isolates from catfish or tilapia obtained from different ponds, irrespective of the type of feed given, may be caused by several factors, such as the quality of the water, density of fish, and size of ponds.

  1. Digital repetitive control under varying frequency conditions

    OpenAIRE

    Ramos Fuentes, Germán Andrés

    2012-01-01

    The tracking/rejection of periodic signals constitutes a wide field of research in the control theory and applications area and Repetitive Control has proven to be an efficient way to face this topic; however, in some applications the period of the signal to be tracked/rejected changes in time or is uncertain, which causes and important performance degradation in the standard repetitive controller. This thesis presents some contributions to the open topic of repetitive control workin...

  2. [Repetition and fear of dying].

    Science.gov (United States)

    Lerner, B D

    1995-03-01

    In this paper a revision is made of the qualifications of Repetition (R) in Freuds work, i.e. its being at the service of the Pleasure Principle and, beyond it, the binding of free energy due to trauma. Freud intends to explain with this last concept the "fort-da" and the traumatic dreams (obsessively reiterated self-reproaches may be added to them). The main thesis of this work is that R. is not only a defense against the recollection of the ominous past (as in the metaphorical deaths of abandonment and desertion) but also a way of maintaining life and identify fighting against the inescapable omninous future (known but yet experienced), i.e. our own death. Some forms of R. like habits, identificatory behaviors and sometimes even magic, are geared to serve the life instinct. A literary illustration shows this desperate fight.

  3. Pressure rig for repetitive casting

    Science.gov (United States)

    Vasquez, Peter (Inventor); Hutto, William R. (Inventor); Philips, Albert R. (Inventor)

    1989-01-01

    The invention is a pressure rig for repetitive casting of metal. The pressure rig performs like a piston for feeding molten metal into a mold. Pressure is applied to an expandable rubber diaphragm which expands like a balloon to force the metal into the mold. A ceramic cavity which holds molten metal is lined with blanket-type insulating material, necessitating only a relining for subsequent use and eliminating the lengthy cavity preparation inherent in previous rigs. In addition, the expandable rubber diaphragm is protected by the insulating material thereby decreasing its vulnerability to heat damage. As a result of the improved design the life expectancy of the pressure rig contemplated by the present invention is more than doubled. Moreover, the improved heat protection has allowed the casting of brass and other alloys with higher melting temperatures than possible in the conventional pressure rigs.

  4. Comparing repetition-based melody segmentation models

    NARCIS (Netherlands)

    Rodríguez López, M.E.; de Haas, Bas; Volk, Anja

    2014-01-01

    This paper reports on a comparative study of computational melody segmentation models based on repetition detection. For the comparison we implemented five repetition-based segmentation models, and subsequently evaluated their capacity to automatically find melodic phrase boundaries in a corpus of 2

  5. Task Repetition and Second Language Speech Processing

    Science.gov (United States)

    Lambert, Craig; Kormos, Judit; Minn, Danny

    2017-01-01

    This study examines the relationship between the repetition of oral monologue tasks and immediate gains in L2 fluency. It considers the effect of aural-oral task repetition on speech rate, frequency of clause-final and midclause filled pauses, and overt self-repairs across different task types and proficiency levels and relates these findings to…

  6. Repetitions: A Cross-Cultural Study.

    Science.gov (United States)

    Murata, Kumiko

    1995-01-01

    This study investigated how repetition is used in conversation among native speakers of British English, native speakers of Japanese, and Japanese speakers of English. Five interactional functions of repetition (interruption-orientated, solidarity, silence-avoidance, hesitation, and reformulation) were identified, as well as the cultural factors…

  7. Digital repetitive control under varying frequency conditions

    CERN Document Server

    Ramos, Germán A; Olm, Josep M

    2013-01-01

    The tracking/rejection of periodic signals constitutes a wide field of research in the control theory and applications area. Repetitive Control has proven to be an efficient way to face this topic. However, in some applications the frequency of the reference/disturbance signal is time-varying or uncertain. This causes an important performance degradation in the standard Repetitive Control scheme. This book presents some solutions to apply Repetitive Control in varying frequency conditions without loosing steady-state performance. It also includes a complete theoretical development and experimental results in two representative systems. The presented solutions are organized in two complementary branches: varying sampling period Repetitive Control and High Order Repetitive Control. The first approach allows dealing with large range frequency variations while the second allows dealing with small range frequency variations. The book also presents applications of the described techniques to a Roto-magnet plant and...

  8. Strategies for Using Repetition as a Powerful Teaching Tool

    Science.gov (United States)

    Saville, Kirt

    2011-01-01

    Brain research indicates that repetition is of vital importance in the learning process. Repetition is an especially useful tool in the area of music education. The success of repetition can be enhanced by accurate and timely feedback. From "simple repetition" to "repetition with the addition or subtraction of degrees of freedom," there are many…

  9. Strategies for Using Repetition as a Powerful Teaching Tool

    Science.gov (United States)

    Saville, Kirt

    2011-01-01

    Brain research indicates that repetition is of vital importance in the learning process. Repetition is an especially useful tool in the area of music education. The success of repetition can be enhanced by accurate and timely feedback. From "simple repetition" to "repetition with the addition or subtraction of degrees of freedom," there are many…

  10. Repetition priming from moving faces.

    Science.gov (United States)

    Lander, Karen; Bruce, Vicki

    2004-06-01

    Recent experiments have suggested that seeing a familiar face move provides additional dynamic information to the viewer, useful in the recognition of identity. In four experiments, repetition priming was used to investigate whether dynamic information is intrinsic to the underlying face representations. The results suggest that a moving image primes more effectively than a static image, even when the same static image is shown in the prime and the test phases (Experiment 1). Furthermore, when moving images are presented in the test phase (Experiment 2), there is an advantage for moving prime images. The most priming advantage is found with naturally moving faces, rather than with those shown in slow motion (Experiment 3). Finally, showing the same moving sequence at prime and test produced more priming than that found when different moving sequences were shown (Experiment 4). The results suggest that dynamic information is intrinsic to the face representations and that there is an advantage to viewing the same moving sequence at prime and test.

  11. Precision markedly attenuates repetitive lift capacity.

    Science.gov (United States)

    Collier, Brooke R; Holland, Laura; McGhee, Deirdre; Sampson, John A; Bell, Alison; Stapley, Paul J; Groeller, Herbert

    2014-01-01

    This study investigated the effect of precision on time to task failure in a repetitive whole-body manual handling task. Twelve participants were required to repetitively lift a box weighing 65% of their single repetition maximum to shoulder height using either precise or unconstrained box placement. Muscle activity, forces exerted at the ground, 2D body kinematics, box acceleration and psychophysical measures of performance were recorded until task failure was reached. With precision, time to task failure for repetitive lifting was reduced by 72%, whereas the duration taken to complete a single lift and anterior deltoid muscle activation increased by 39% and 25%, respectively. Yet, no significant difference was observed in ratings of perceived exertion or heart rate at task failure. In conclusion, our results suggest that when accuracy is a characteristic of a repetitive manual handling task, physical work capacity will decline markedly. The capacity to lift repetitively to shoulder height was reduced by 72% when increased accuracy was required to place a box upon a shelf. Lifting strategy and muscle activity were also modified, confirming practitioners should take into consideration movement precision when evaluating the demands of repetitive manual handling tasks.

  12. Repetitive Bibliographical Information in Relational Databases.

    Science.gov (United States)

    Brooks, Terrence A.

    1988-01-01

    Proposes a solution to the problem of loading repetitive bibliographic information in a microcomputer-based relational database management system. The alternative design described is based on a representational redundancy design and normalization theory. (12 references) (Author/CLB)

  13. Computer-Related Repetitive Stress Injuries

    Science.gov (United States)

    ... on the shoulder Epicondylitis: elbow soreness often called "tennis elbow" Ganglion cyst: swelling or lump in the wrist ... Bones, Muscles, and Joints Carpal Tunnel Syndrome Medial Epicondylitis Repetitive Stress Injuries Contact Us Print Resources Send ...

  14. Digital repetitive control under varying frequency conditions

    OpenAIRE

    Ramos Fuentes, Germán Andrés

    2012-01-01

    Premi extraordinari doctorat curs 2011-2012, àmbit d’Enginyeria Industrial The tracking/rejection of periodic signals constitutes a wide field of research in the control theory and applications area and Repetitive Control has proven to be an efficient way to face this topic; however, in some applications the period of the signal to be tracked/rejected changes in time or is uncertain, which causes and important performance degradation in the standard repetitive controller. This the...

  15. The Prevalence and Phenomenology of Repetitive Behavior in Genetic Syndromes

    Science.gov (United States)

    Moss, Joanna; Oliver, Chris; Arron, Kate; Burbidge, Cheryl; Berg, Katy

    2009-01-01

    We investigated the prevalence and phenomenology of repetitive behavior in genetic syndromes to detail profiles of behavior. The Repetitive Behaviour Questionnaire (RBQ) provides fine-grained identification of repetitive behaviors. The RBQ was employed to examine repetitive behavior in Angelman (N = 104), Cornelia de Lange (N = 101), Cri-du-Chat…

  16. Likelihood methods and classical burster repetition

    CERN Document Server

    Graziani, C; Graziani, Carlo; Lamb, Donald Q

    1995-01-01

    We develop a likelihood methodology which can be used to search for evidence of burst repetition in the BATSE catalog, and to study the properties of the repetition signal. We use a simplified model of burst repetition in which a number N_{\\rm r} of sources which repeat a fixed number of times N_{\\rm rep} are superposed upon a number N_{\\rm nr} of non-repeating sources. The instrument exposure is explicitly taken into account. By computing the likelihood for the data, we construct a probability distribution in parameter space that may be used to infer the probability that a repetition signal is present, and to estimate the values of the repetition parameters. The likelihood function contains contributions from all the bursts, irrespective of the size of their positional errors --- the more uncertain a burst's position is, the less constraining is its contribution. Thus this approach makes maximal use of the data, and avoids the ambiguities of sample selection associated with data cuts on error circle size. We...

  17. The neurobiology of repetitive behavior : of mice…

    NARCIS (Netherlands)

    Langen, Marieke; Kas, Martien J H; Staal, Wouter G; van Engeland, Herman; Durston, Sarah

    2011-01-01

    Repetitive and stereotyped behavior is a prominent element of both animal and human behavior. Similar behavior is seen across species, in diverse neuropsychiatric disorders and in key phases of typical development. This raises the question whether these similar classes of behavior are caused by simi

  18. Large-scale detection of repetitions.

    Science.gov (United States)

    Smyth, W F

    2014-05-28

    Combinatorics on words began more than a century ago with a demonstration that an infinitely long string with no repetitions could be constructed on an alphabet of only three letters. Computing all the repetitions (such as ∙∙∙TTT ∙∙∙ or ∙∙∙ CGACGA ∙∙∙ ) in a given string x of length n is one of the oldest and most important problems of computational stringology, requiring time in the worst case. About a dozen years ago, it was discovered that repetitions can be computed as a by-product of the Θ(n)-time computation of all the maximal periodicities or runs in x. However, even though the computation is linear, it is also brute force: global data structures, such as the suffix array, the longest common prefix array and the Lempel-Ziv factorization, need to be computed in a preprocessing phase. Furthermore, all of this effort is required despite the fact that the expected number of runs in a string is generally a small fraction of the string length. In this paper, I explore the possibility that repetitions (perhaps also other regularities in strings) can be computed in a manner commensurate with the size of the output.

  19. Verbal Repetitions and Echolalia in Alzheimer's Discourse

    Science.gov (United States)

    Da Cruz, Fernanda Miranda

    2010-01-01

    This article reports on an investigation of echolalic repetition in Alzheimer's disease (AD). A qualitative analysis of data from spontaneous conversations with MHI, a woman with AD, is presented. The data come from the DALI Corpus, a corpus of spontaneous conversations involving subjects with AD. This study argues that echolalic effects can be…

  20. Neurobehavioural Correlates of Abnormal Repetitive Behaviour

    Directory of Open Access Journals (Sweden)

    R. A. Ford

    1991-01-01

    Full Text Available Conditions in which echolalia and echopraxia occur are reviewed, followed by an attempt to elicit possible mechanisms of these phenomena. A brief description of stereotypical and perseverative behaviour and obsessional phenomena is given. It is suggested that abnormal repetitive behaviour may occur partly as a result of central dopaminergic dysfunction.

  1. Reducing Repetitive Speech: Effects of Strategy Instruction.

    Science.gov (United States)

    Dipipi, Caroline M.; Jitendra, Asha K.; Miller, Judith A.

    2001-01-01

    This article describes an intervention with an 18-year-old young woman with mild mental retardation and a seizure disorder, which focused on her repetitive echolalic verbalizations. The intervention included time delay, differential reinforcement of other behaviors, and self-monitoring. Overall, the intervention was successful in facilitating…

  2. Verbal Repetitions and Echolalia in Alzheimer's Discourse

    Science.gov (United States)

    Da Cruz, Fernanda Miranda

    2010-01-01

    This article reports on an investigation of echolalic repetition in Alzheimer's disease (AD). A qualitative analysis of data from spontaneous conversations with MHI, a woman with AD, is presented. The data come from the DALI Corpus, a corpus of spontaneous conversations involving subjects with AD. This study argues that echolalic effects can be…

  3. Robust Repetitive Controller for Fast AFM Imaging

    CERN Document Server

    Necipoglu, Serkan; Has, Yunus; Guvenc, Levent; Basdogan, Cagatay

    2012-01-01

    Currently, Atomic Force Microscopy (AFM) is the most preferred Scanning Probe Microscopy (SPM) method due to its numerous advantages. However, increasing the scanning speed and reducing the interaction forces between the probe's tip and the sample surface are still the two main challenges in AFM. To meet these challenges, we take advantage of the fact that the lateral movements performed during an AFM scan is a repetitive motion and propose a Repetitive Controller (RC) for the z-axis movements of the piezo-scanner. The RC utilizes the profile of the previous scan line while scanning the current line to achieve a better scan performance. The results of the scanning experiments performed with our AFM set-up show that the proposed RC significantly outperforms a conventional PI controller that is typically used for the same task. The scan error and the average tapping forces are reduced by 66% and 58%, respectively when the scan speed is increased by 7-fold.

  4. A repetitive elements perspective in Polycomb epigenetics.

    Directory of Open Access Journals (Sweden)

    Valentina eCasa

    2012-10-01

    Full Text Available Repetitive elements comprise over two-thirds of the human genome. For a long time, these elements have received little attention since they were considered non functional. On the contrary, recent evidence indicates that they play central roles in genome integrity, gene expression and disease. Indeed, repeats display meiotic instability associated with disease and are located within common fragile sites, which are hotspots of chromosome rearrangements in tumors. Moreover, a variety of diseases have been associated with aberrant transcription of repetitive elements. Overall this indicates that appropriate regulation of repetitive elements’ activity is fundamental.Polycomb group (PcG proteins are epigenetic regulators that are essential for the normal development of multicellular organisms. Mammalian PcG proteins are involved in fundamental processes, such as cellular memory, cell proliferation, genomic imprinting, X-inactivation, and cancer development. PcG proteins can convey their activity through long-distance interactions also on different chromosomes. This indicates that the 3D organization of PcG proteins contributes significantly to their function. However, it is still unclear how these complex mechanisms are orchestrated and which role PcG proteins play in the multi-level organization of gene regulation. Intriguingly, the greatest proportion of Polycomb-mediated chromatin modifications is located in genomic repeats and it has been suggested that they could provide a binding platform for Polycomb proteins.Here, these lines of evidence are woven together to discuss how repetitive elements could contribute to chromatin organization in the 3D nuclear space.

  5. Emotional arousal enhances word repetition priming

    OpenAIRE

    Thomas, Laura A.; LaBar, Kevin S.

    2005-01-01

    Three experiments were conducted to determine if emotional content increases repetition priming magnitude. In the study phase of Experiment 1, participants rated high-arousing negative (taboo) words and neutral words for concreteness. In the test phase, they made lexical decision judgements for the studied words intermixed with novel words (half taboo, half neutral) and pseudowords. In Experiment 2, low-arousing negative (LAN) words were substituted for the taboo words, and in Experiment 3 al...

  6. The Rhythms of Echo. Variations on Repetition

    Directory of Open Access Journals (Sweden)

    Rosa María Aradra Sánchez

    2015-04-01

    Full Text Available This paper presents a study on the echo as metric and rhetorical procedure. It makes a brief tour through some of the poetic manifestations of echo in the Spanish literary tradition, and a brief tour through the attention that metric theory has paid to this phenomenon. Then it stops at the possibilities that rhetoric offers for its analysis from the generic approach of the discursive repetition phenomena.

  7. Repetitive behaviour in autism: Imaging pathways and trajectories

    NARCIS (Netherlands)

    Langen, M.J.G.

    2009-01-01

    Repetitive behaviour in autism: Imaging pathways and trajectories Repetitive and rigid behaviour is one of the core symptoms of autism, a severe and lifelong child psychiatric disorder. Although repetitive behaviour symptoms often form a significant impairment for affected individuals, systematic st

  8. Neural Correlates of Restricted, Repetitive Behaviors in Autism Spectrum Disorders

    Science.gov (United States)

    2014-12-01

    Restrictive Repetitive Behaviors in Autism Spectrum Disorder . Authors: T.Q.Nguyen, B...Manoach. Functional Connectivity of the Dorsal Anterior Cingulate Cortex Predicts Restrictive Repetitive Behaviors in Autism Spectrum Disorder We...Introduction: Although restricted , repetitive behaviors (RRBs) are a highly disabling core feature of Autism Spectrum Disorders (ASDs), they

  9. Lingual Kinematics during Rapid Syllable Repetition in Parkinson's Disease

    Science.gov (United States)

    Wong, Min Ney; Murdoch, Bruce E.; Whelan, Brooke-Mai

    2012-01-01

    Background: Rapid syllable repetition tasks are commonly used in the assessment of motor speech disorders. However, little is known about the articulatory kinematics during rapid syllable repetition in individuals with Parkinson's disease (PD). Aims: To investigate and compare lingual kinematics during rapid syllable repetition in dysarthric…

  10. Repetitive Elements in Mycoplasma hyopneumoniae Transcriptional Regulation

    Science.gov (United States)

    Cattani, Amanda Malvessi; Siqueira, Franciele Maboni; Guedes, Rafael Lucas Muniz; Schrank, Irene Silveira

    2016-01-01

    Transcriptional regulation, a multiple-step process, is still poorly understood in the important pig pathogen Mycoplasma hyopneumoniae. Basic motifs like promoters and terminators have already been described, but no other cis-regulatory elements have been found. DNA repeat sequences have been shown to be an interesting potential source of cis-regulatory elements. In this work, a genome-wide search for tandem and palindromic repetitive elements was performed in the intergenic regions of all coding sequences from M. hyopneumoniae strain 7448. Computational analysis demonstrated the presence of 144 tandem repeats and 1,171 palindromic elements. The DNA repeat sequences were distributed within the 5’ upstream regions of 86% of transcriptional units of M. hyopneumoniae strain 7448. Comparative analysis between distinct repetitive sequences found in related mycoplasma genomes demonstrated different percentages of conservation among pathogenic and nonpathogenic strains. qPCR assays revealed differential expression among genes showing variable numbers of repetitive elements. In addition, repeats found in 206 genes already described to be differentially regulated under different culture conditions of M. hyopneumoniae strain 232 showed almost 80% conservation in relation to M. hyopneumoniae strain 7448 repeats. Altogether, these findings suggest a potential regulatory role of tandem and palindromic DNA repeats in the M. hyopneumoniae transcriptional profile. PMID:28005945

  11. Modeling repetitive motions using structured light.

    Science.gov (United States)

    Xu, Yi; Aliaga, Daniel G

    2010-01-01

    Obtaining models of dynamic 3D objects is an important part of content generation for computer graphics. Numerous methods have been extended from static scenarios to model dynamic scenes. If the states or poses of the dynamic object repeat often during a sequence (but not necessarily periodically), we call such a repetitive motion. There are many objects, such as toys, machines, and humans, undergoing repetitive motions. Our key observation is that when a motion-state repeats, we can sample the scene under the same motion state again but using a different set of parameters; thus, providing more information of each motion state. This enables robustly acquiring dense 3D information difficult for objects with repetitive motions using only simple hardware. After the motion sequence, we group temporally disjoint observations of the same motion state together and produce a smooth space-time reconstruction of the scene. Effectively, the dynamic scene modeling problem is converted to a series of static scene reconstructions, which are easier to tackle. The varying sampling parameters can be, for example, structured-light patterns, illumination directions, and viewpoints resulting in different modeling techniques. Based on this observation, we present an image-based motion-state framework and demonstrate our paradigm using either a synchronized or an unsynchronized structured-light acquisition method.

  12. Repetitive element hypermethylation in multiple sclerosis patients.

    Science.gov (United States)

    Neven, K Y; Piola, M; Angelici, L; Cortini, F; Fenoglio, C; Galimberti, D; Pesatori, A C; Scarpini, E; Bollati, V

    2016-06-18

    Multiple sclerosis (MS) is a complex disorder of the central nervous system whose cause is currently unknown. Evidence is increasing that DNA methylation alterations could be involved in inflammatory and neurodegenerative diseases and could contribute to MS pathogenesis. Repetitive elements Alu, LINE-1 and SAT-α, are widely known as estimators of global DNA methylation. We investigated Alu, LINE-1 and SAT-α methylation levels to evaluate their difference in a case-control setup and their role as a marker of disability. We obtained blood samples from 51 MS patients and 137 healthy volunteers matched by gender, age and smoking. Methylation was assessed using bisulfite-PCR-pyrosequencing. For all participants, medical history, physical and neurological examinations and screening laboratory tests were collected. All repetitive elements were hypermethylated in MS patients compared to healthy controls. A lower Expanded Disability Status Scale (EDSS) score was associated with a lower levels of LINE-1 methylation for 'EDSS = 1.0' and '1.5 ≤ EDSS ≤ 2.5' compared to an EDSS higher than 3, while Alu was associated with a higher level of methylation in these groups: 'EDSS = 1.0' and '1.5 ≤ EDSS ≤ 2.5'. MS patients exhibit an hypermethylation in repetitive elements compared to healthy controls. Alu and LINE-1 were associated with degree of EDSS score. Forthcoming studies focusing on epigenetics and the multifactorial pathogenetic mechanism of MS could elucidate these links further.

  13. FRB repetition and non-Poissonian statistics

    CERN Document Server

    Connor, Liam; Oppermann, Niels

    2016-01-01

    We discuss some of the claims that have been made regarding the statistics of fast radio bursts (FRBs). In an earlier paper \\citep{2015arXiv150505535C} we conjectured that flicker noise associated with FRB repetition could show up in non-cataclysmic neutron star emission models, like supergiant pulses. We show how the current limits of repetition would be significantly weakened if their repeat rate really were non-Poissonian and had a pink or red spectrum. Repetition and its statistics have implications for observing strategy, generally favouring shallow wide-field surveys, since in the non-repeating scenario survey depth is unimportant. We also discuss the statistics of the apparent latitudinal dependence of FRBs, and offer a simple method for calculating the significance of this effect. We provide a generalized Bayesian framework for addressing this problem, which allows for direct model comparison. It is shown how the evidence for a steep latitudinal gradient of the FRB rate is less strong than initially s...

  14. fMRI repetition suppression: neuronal adaptation or stimulus expectation?

    Science.gov (United States)

    Larsson, Jonas; Smith, Andrew T

    2012-03-01

    Measurements of repetition suppression with functional magnetic resonance imaging (fMRI adaptation) have been used widely to probe neuronal population response properties in human cerebral cortex. fMRI adaptation techniques assume that fMRI repetition suppression reflects neuronal adaptation, an assumption that has been challenged on the basis of evidence that repetition-related response changes may reflect unrelated factors, such as attention and stimulus expectation. Specifically, Summerfield et al. (Summerfield C, Trittschuh EH, Monti JM, Mesulam MM, Egner T. 2008. Neural repetition suppression reflects fulfilled perceptual expectations. Nat Neurosci. 11:1004-1006) reported that the relative frequency of stimulus repetitions and non-repetitions influenced the magnitude of repetition suppression in the fusiform face area, suggesting that stimulus expectation accounted for most of the effect of repetition. We confirm that stimulus expectation can significantly influence fMRI repetition suppression throughout visual cortex and show that it occurs with long as well as short adaptation durations. However, the effect was attention dependent: When attention was diverted away from the stimuli, the effects of stimulus expectation completely disappeared. Nonetheless, robust and significant repetition suppression was still evident. These results suggest that fMRI repetition suppression reflects a combination of neuronal adaptation and attention-dependent expectation effects that can be experimentally dissociated. This implies that with an appropriate experimental design, fMRI adaptation can provide valid measures of neuronal adaptation and hence response specificity.

  15. Storytelling and Repetitive Narratives for Design Empathy

    DEFF Research Database (Denmark)

    Fritsch, Jonas; Judice, Andrea; Soini, Katja

    2007-01-01

    Today it is widely established in design research that empathy is an important part of creating a true understanding of user experience as a resource for design. A typical challenge is how to transmit the feeling of empathy acquired by user studies to designers who have not participated in the user...... study. In this paper, we show how we attained an empathic understanding through storytelling and aroused empathy to others using repetitive narratives in an experimental presentation bringing forth factual, reflective and experiential aspects of the user information. Taking as a starting point our...... experiences with the design project Suomenlinna Seclusive, we conclude with the potential of using narratives for invoking design empathy....

  16. A miniature high repetition rate shock tube.

    Science.gov (United States)

    Tranter, R S; Lynch, P T

    2013-09-01

    A miniature high repetition rate shock tube with excellent reproducibility has been constructed to facilitate high temperature, high pressure, gas phase experiments at facilities such as synchrotron light sources where space is limited and many experiments need to be averaged to obtain adequate signal levels. The shock tube is designed to generate reaction conditions of T > 600 K, P shock waves with predictable characteristics are created, repeatably. Two synchrotron-based experiments using this apparatus are also briefly described here, demonstrating the potential of the shock tube for research at synchrotron light sources.

  17. Storytelling and Repetitive Narratives for Design Empathy

    DEFF Research Database (Denmark)

    Fritsch, Jonas; Judice, Andrea; Soini, Katja

    2007-01-01

    Today it is widely established in design research that empathy is an important part of creating a true understanding of user experience as a resource for design. A typical challenge is how to transmit the feeling of empathy acquired by user studies to designers who have not participated in the user...... study. In this paper, we show how we attained an empathic understanding through storytelling and aroused empathy to others using repetitive narratives in an experimental presentation bringing forth factual, reflective and experiential aspects of the user information. Taking as a starting point our...... experiences with the design project Suomenlinna Seclusive, we conclude with the potential of using narratives for invoking design empathy....

  18. The repetitive component of the sunflower genome

    Directory of Open Access Journals (Sweden)

    T. Giordani

    2014-08-01

    Full Text Available The sunflower (Helianthus annuus and species belonging to the genus Helianthus are emerging as a model species and genus for a number of studies on genome evolution. In this review, we report on the repetitive component of the H. annuus genome at the biochemical, molecular, cytological, and genomic levels. Recent work on sunflower genome composition is described, with emphasis on different types of repeat sequences, especially LTR-retrotransposons, of which we report on isolation, characterisation, cytological localisation, transcription, dynamics of proliferation, and comparative analyses within the genus Helianthus.

  19. Dynamics and Diversity of Escherichia coli in Animals and System Management of the Manure on a Commercial Farrow-to-Finish Pig Farm

    Science.gov (United States)

    Marchant, Mauricio

    2013-01-01

    The objective of this study was to determine the dynamics and diversity of Escherichia coli populations in animal and environmental lines of a commercial farrow-to-finish pig farm in Spain along a full production cycle (July 2008 to July 2009), with special attention to antimicrobial resistance and the presence of integrons. In the animal line, a total of 256 isolates were collected from pregnant sows (10 samples and 20 isolates), 1-week-old piglets (20 samples and 40 isolates), unweaned piglets (20 samples and 38 isolates), growers (20 samples and 40 isolates), and the finishers' floor pen (6 samples and 118 isolates); from the underfloor pits and farm slurry tank environmental lines, 100 and 119 isolates, respectively, were collected. Our results showed that E. coli populations in the pig fecal microbiota and in the farm environment are highly dynamic and show high levels of diversity. These issues have been proven through DNA-based typing data (repetitive extragenic palindromic PCR [REP-PCR]) and phenotypic typing data (antimicrobial resistance profile comprising 19 antimicrobials). Clustering of the sampling groups based on their REP-PCR typing results showed that the spatial features (the line) had a stronger weight than the temporal features (sampling week) for the clustering of E. coli populations; this weight was less significant when clustering was performed based on resistotypes. Among animals, finishers harbored an E. coli population different from those of the remaining animal populations studied, considering REP-PCR fingerprints and resistotypes. This population, the most important from a public health perspective, demonstrated the lowest levels of antimicrobial resistance and integron presence. PMID:23160136

  20. Utility of Whole-Genome Sequencing in Characterizing Acinetobacter Epidemiology and Analyzing Hospital Outbreaks.

    Science.gov (United States)

    Fitzpatrick, Margaret A; Ozer, Egon A; Hauser, Alan R

    2016-03-01

    Acinetobacter baumannii frequently causes nosocomial infections and outbreaks. Whole-genome sequencing (WGS) is a promising technique for strain typing and outbreak investigations. We compared the performance of conventional methods with WGS for strain typing clinical Acinetobacter isolates and analyzing a carbapenem-resistant A. baumannii (CRAB) outbreak. We performed two band-based typing techniques (pulsed-field gel electrophoresis and repetitive extragenic palindromic-PCR), multilocus sequence type (MLST) analysis, and WGS on 148 Acinetobacter calcoaceticus-A. baumannii complex bloodstream isolates collected from a single hospital from 2005 to 2012. Phylogenetic trees inferred from core-genome single nucleotide polymorphisms (SNPs) confirmed three Acinetobacter species within this collection. Four major A. baumannii clonal lineages (as defined by MLST) circulated during the study, three of which are globally distributed and one of which is novel. WGS indicated that a threshold of 2,500 core SNPs accurately distinguished A. baumannii isolates from different clonal lineages. The band-based techniques performed poorly in assigning isolates to clonal lineages and exhibited little agreement with sequence-based techniques. After applying WGS to a CRAB outbreak that occurred during the study, we identified a threshold of 2.5 core SNPs that distinguished nonoutbreak from outbreak strains. WGS was more discriminatory than the band-based techniques and was used to construct a more accurate transmission map that resolved many of the plausible transmission routes suggested by epidemiologic links. Our study demonstrates that WGS is superior to conventional techniques for A. baumannii strain typing and outbreak analysis. These findings support the incorporation of WGS into health care infection prevention efforts.

  1. Site-specific distribution and competitive ability of indigenous bean-nodulating rhizobia isolated from organic fields in Minnesota.

    Science.gov (United States)

    Wongphatcharachai, Manoosak; Wang, Ping; Staley, Christopher; Chun, Chan Lan; Ferguson, John A; Moncada, Kristine M; Sheaffer, Craig C; Sadowsky, Michael J

    2015-11-20

    Organic dry bean production systems have received increasing interest in many regions of the US, including Minnesota. Thus, improving biological N2 fixation would be highly beneficial for organic crop production. To date, only limited work has been done to select efficient N2-fixing rhizobia for organic dry bean production. In this study, soil samples from 25 organic fields in Minnesota, with a previous cropping history of dry beans, soybeans or both, were collected during May to July 2012. Genetic diversity of indigenous dry bean-rhizobia (511 isolates) was determined by using horizontal, fluorophore-enhanced, repetitive, extragenic, and palindromic-PCR (HFERP) DNA fingerprinting and isolates were classified as belonging to 58 different genotypes. The more abundant rhizobia isolated from bean nodules comprised 35.6% of the population. None of the isolates were identical to commonly-used commercial strains used in the U.S., including Rhizobium tropici CIAT899. Seventeen predominant genotypes were shown to represent two main species, Rhizobium leguminosarum bv. phaseoli (67.1%) and Rhizobium etli (30.2%). One of the indigenous strains, orgK9, displayed efficient N2-fixation and competitive ability relative to the commercial strains tested. The lack of large numbers of indigenous dry bean-rhizobia at most study sites will be useful to avoid competition problems between inoculant strains and indigenous rhizobia. This will allow inoculation with highly effective N2-fixing rhizobia, thus resulting in improved crop productivity. Our results highlight the existence of site-specific rhizobial genotypes in different organic fields and identify strains that may prove useful as novel inoculants for organic dry bean production systems. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Genetic Diversity and Evidence for Transmission of Streptococcus mutans by DiversiLab rep-PCR.

    Science.gov (United States)

    Momeni, Stephanie S; Whiddon, Jennifer; Cheon, Kyounga; Ghazal, Tariq; Moser, Stephen A; Childers, Noel K

    2016-09-01

    This two-part study investigated the genetic diversity and transmission of Streptococcus mutans using the DiversiLab repetitive extragenic palindromic PCR (rep-PCR) approach. For children with S. mutans and participating household members, analysis for evidence of unrelated child-to-child as well as intra-familial transmission was evaluated based on commonality of genotypes. A total of 169 index children and 425 household family members from Uniontown, Alabama were evaluated for genetic diversity using rep-PCR. Thirty-four unique rep-PCR genotypes were observed for 13,906 S. mutans isolates. For transmission, 117 child and household isolates were evaluated for shared genotype (by child and by genotype cases, multiple matches possible for each child). Overall, children had 1-9 genotypes and those with multiple genotypes were 2.3 times more likely to have caries experience (decayed, missing and filled teeth/surfaces>0). Only 28% of children shared all genotypes within the household, while 72% had at least 1 genotype not shared with anyone in the household. Children had genotype(s) not shared with any household members in 157 cases. In 158 cases children and household members shared a genotype in which 55% (87/158 cases) were shared with more than one family member. Children most frequently shared genotypes with their mothers (54%; 85/158), siblings (46%; 72/158) and cousins (23%; 37/158). A reference library for S. mutans for epidemiological surveillance using the DiversiLab rep-PCR approach is detailed. The genetic diversity of S. mutans in this population demonstrated frequent commonality of genotypes. Evidence for both child-to-child and intra-familial transmission of S. mutans was observed by rep-PCR.

  3. Population structure of clinical and environmental Vibrio parahaemolyticus from the Pacific Northwest coast of the United States.

    Directory of Open Access Journals (Sweden)

    Jeffrey W Turner

    Full Text Available Vibrio parahaemolyticus is a common marine bacterium and a leading cause of seafood-borne bacterial gastroenteritis worldwide. Although this bacterium has been the subject of much research, the population structure of cold-water populations remains largely undescribed. We present a broad phylogenetic analysis of clinical and environmental V. parahaemolyticus originating largely from the Pacific Northwest coast of the United States. Repetitive extragenic palindromic PCR (REP-PCR separated 167 isolates into 39 groups and subsequent multilocus sequence typing (MLST separated a subset of 77 isolates into 24 sequence types. The Pacific Northwest population exhibited a semi-clonal structure attributed to an environmental clade (ST3, N = 17 isolates clonally related to the pandemic O3:K6 complex and a clinical clade (ST36, N = 20 isolates genetically related to a regionally endemic O4:K12 complex. Further, the identification of at least five additional clinical sequence types (i.e., ST43, 50, 65, 135 and 417 demonstrates that V. parahaemolyticus gastroenteritis in the Pacific Northwest is polyphyletic in nature. Recombination was evident as a significant source of genetic diversity and in particular, the recA and dtdS alleles showed strong support for frequent recombination. Although pandemic-related illnesses were not documented during the study, the environmental occurrence of the pandemic clone may present a significant threat to human health and warrants continued monitoring. It is evident that V. parahaemolyticus population structure in the Pacific Northwest is semi-clonal and it would appear that multiple sequence types are contributing to the burden of disease in this region.

  4. The role of short-term memory impairment in nonword repetition, real word repetition, and nonword decoding: A case study.

    Science.gov (United States)

    Peter, Beate

    2017-09-21

    In a companion study, adults with dyslexia and adults with a probable history of childhood apraxia of speech showed evidence of difficulty with processing sequential information during nonword repetition, multisyllabic real word repetition and nonword decoding. Results suggested that some errors arose in visual encoding during nonword reading, all levels of processing but especially short-term memory storage/retrieval during nonword repetition, and motor planning and programming during complex real word repetition. To further investigate the role of short-term memory, a participant with short-term memory impairment (MI) was recruited. MI was confirmed with poor performance during a sentence repetition and three nonword repetition tasks, all of which have a high short-term memory load, whereas typical performance was observed during tests of reading, spelling, and static verbal knowledge, all with low short-term memory loads. Experimental results show error-free performance during multisyllabic real word repetition but high counts of sequence errors, especially migrations and assimilations, during nonword repetition, supporting short-term memory as a locus of sequential processing deficit during nonword repetition. Results are also consistent with the hypothesis that during complex real word repetition, short-term memory is bypassed as the word is recognized and retrieved from long-term memory prior to producing the word.

  5. A phonetic approach to consonant repetition in early words.

    Science.gov (United States)

    Kim, Namhee; Davis, Barbara L

    2015-08-01

    The goal of this study was to evaluate movement-based principles for understanding early speech output patterns. Consonant repetition patterns within children's actual productions of word forms were analyzed using spontaneous speech data from 10 typically developing American-English learning children between 12 and 36 months of age. Place of articulation, word level patterns, and developmental trends in CVC and CVCV repeated word forms were evaluated. Labial and coronal place repetitions dominated. Regressive repetition (e.g., [gag] for "dog") occurred frequently in CVC but not in CVCV word forms. Consonant repetition decreased over time. However, the children produced sound types available reported as being within young children's production system capabilities in consonant repetitions in all time periods. Findings suggest that a movement-based approach can provide a framework for comprehensively characterizing consonant place repetition patterns in early speech development.

  6. Repetition and Reactance in Graham’s "Underneath" Poems

    Directory of Open Access Journals (Sweden)

    Roghayeh Farsi

    2017-09-01

    Full Text Available The present paper gives a detailed analysis and interpretation of 16 poems in Jorie Graham's collection, Swarm (2000, which bear "UNDERNEATH" as their main titles. The poems are marked with different types of repetition such as graphological repetition, word, phrase, and sentential repetition, semantic repetition, and syntactic repetition. The study draws on Lakoff and Johnson's theories on metaphor and Brehm and Brehm’s reactance theory. It is argued "underneath" is a conceptual (orientational metaphor which signifies a state of being limited, lack of control and freedom, and loss of power. The paper investigates the speaker's reactant behavior in "Underneath" poems, seeking a way to restore her lost freedom. Reactance behaviors can be skepticism, inertia, aggression, and resistance. It is concluded despite her thematic inertia, representing her submission to the oppressed state, her stylistic reactance reflected in repetitions, innovations, and disruptive diction stands for her attempts to regain her lost control.

  7. FEMA Hazard Mitigation Assistance Repetitive Flood Claims (RFC) Data

    Data.gov (United States)

    Department of Homeland Security — This dataset contains closed and obligated projects funded under the following Hazard Mitigation Assistance (HMA) grant programs: Repetitive Flood Claims (RFC). The...

  8. A review of neuroimaging findings in repetitive brain trauma.

    Science.gov (United States)

    Koerte, Inga K; Lin, Alexander P; Willems, Anna; Muehlmann, Marc; Hufschmidt, Jakob; Coleman, Michael J; Green, Isobel; Liao, Huijun; Tate, David F; Wilde, Elisabeth A; Pasternak, Ofer; Bouix, Sylvain; Rathi, Yogesh; Bigler, Erin D; Stern, Robert A; Shenton, Martha E

    2015-05-01

    Chronic traumatic encephalopathy (CTE) is a neurodegenerative disease confirmed at postmortem. Those at highest risk are professional athletes who participate in contact sports and military personnel who are exposed to repetitive blast events. All neuropathologically confirmed CTE cases, to date, have had a history of repetitive head impacts. This suggests that repetitive head impacts may be necessary for the initiation of the pathogenetic cascade that, in some cases, leads to CTE. Importantly, while all CTE appears to result from repetitive brain trauma, not all repetitive brain trauma results in CTE. Magnetic resonance imaging has great potential for understanding better the underlying mechanisms of repetitive brain trauma. In this review, we provide an overview of advanced imaging techniques currently used to investigate brain anomalies. We also provide an overview of neuroimaging findings in those exposed to repetitive head impacts in the acute/subacute and chronic phase of injury and in more neurodegenerative phases of injury, as well as in military personnel exposed to repetitive head impacts. Finally, we discuss future directions for research that will likely lead to a better understanding of the underlying mechanisms separating those who recover from repetitive brain trauma vs. those who go on to develop CTE.

  9. FEMA Hazard Mitigation Assistance Severe Repetitive Loss (SRL) Data

    Data.gov (United States)

    Department of Homeland Security — This dataset contains closed and obligated projects funded under the following Hazard Mitigation Assistance (HMA) grant programs: Severe Repetitive Loss (SRL). The...

  10. Repetitive control of electrically driven robot manipulators

    Science.gov (United States)

    Fateh, Mohammad Mehdi; Ahsani Tehrani, Hojjat; Karbassi, Seyed Mehdi

    2013-04-01

    This article presents a novel robust discrete repetitive control of electrically driven robot manipulators for tracking of a periodic trajectory. We propose a novel model, which presents the highly non-linear dynamics of robot manipulator in the form of linear discrete-time time-varying system. Based on the proposed model, we develop a two-term control law. The first term is an ordinary time-optimal and minimum-norm (TOMN) control by employing parametric controllers to guarantee stability. The second term is a novel robust control to improve the control performance in the face of uncertainties. The robust control estimates and compensates uncertainties including the parametric uncertainty, unmodelled dynamics and external disturbances. Performance of the proposed method is compared with two discrete methods, namely the TOMN control and an adaptive iterative learning (AIL) control. Simulation results confirm superiority of the proposed method in terms of the convergence speed and precision.

  11. Studies of the uncanny: the repetition factor

    Directory of Open Access Journals (Sweden)

    Julia Teitelroit Martins

    2011-06-01

    Full Text Available Freud’s essay The Uncanny (Das Unheimliche offers many indications for the comprehension of an aesthetics of the uncanny which deserve to be explored. Nonetheless, a concept traverses it from beginning to end: the return – which enables its reading under the light of Beyond the pleasure principle, written along the same span of time. Emphasis is given to the uncanny in the sense of repetition of the different – a paradox in terms, like the strangely familiar uncanny. In order to test the validity of an aesthetic reading under this perspective, follows an analysis of the brief short story “A terceira margem do rio” (“The third margin of the river”, by Guimarães Rosa.

  12. Object color affects identification and repetition priming.

    Science.gov (United States)

    Uttl, Bob; Graf, Peter; Santacruz, Pilar

    2006-10-01

    We investigated the influence of color on the identification of both non-studied and studied objects. Participants studied black and white and color photos of common objects and memory was assessed with an identification test. Consistent with our meta-analysis of prior research, we found that objects were easier to identify from color than from black and white photos. We also found substantial priming in all conditions, and study-to-test changes in an object's color reduced the magnitude of priming. Color-specific priming effects were large for color-complex objects, but minimal for color-simple objects. The pattern and magnitude of priming effects was not influenced either by the extent to which an object always appears in the same color (i.e., whether a color is symptomatic of an object) or by the object's origin (natural versus fabricated). We discuss the implications of our findings for theoretical accounts of object perception and repetition priming.

  13. The golden ratio of gait harmony: repetitive proportions of repetitive gait phases.

    Science.gov (United States)

    Iosa, Marco; Fusco, Augusto; Marchetti, Fabio; Morone, Giovanni; Caltagirone, Carlo; Paolucci, Stefano; Peppe, Antonella

    2013-01-01

    In nature, many physical and biological systems have structures showing harmonic properties. Some of them were found related to the irrational number φ known as the golden ratio that has important symmetric and harmonic properties. In this study, the spatiotemporal gait parameters of 25 healthy subjects were analyzed using a stereophotogrammetric system with 25 retroreflective markers located on their skin. The proportions of gait phases were compared with φ, the value of which is about 1.6180. The ratio between the entire gait cycle and stance phase resulted in 1.620 ± 0.058, that between stance and the swing phase was 1.629 ± 0.173, and that between swing and the double support phase was 1.684 ± 0.357. All these ratios did not differ significantly from each other (F = 0.870, P = 0.422, repeated measure analysis of variance) or from φ (P = 0.670, 0.820, 0.422, resp., t-tests). The repetitive gait phases of physiological walking were found in turn in repetitive proportions with each other, revealing an intrinsic harmonic structure. Harmony could be the key for facilitating the control of repetitive walking. Harmony is a powerful unifying factor between seemingly disparate fields of nature, including human gait.

  14. The Golden Ratio of Gait Harmony: Repetitive Proportions of Repetitive Gait Phases

    Directory of Open Access Journals (Sweden)

    Marco Iosa

    2013-01-01

    Full Text Available In nature, many physical and biological systems have structures showing harmonic properties. Some of them were found related to the irrational number known as the golden ratio that has important symmetric and harmonic properties. In this study, the spatiotemporal gait parameters of 25 healthy subjects were analyzed using a stereophotogrammetric system with 25 retroreflective markers located on their skin. The proportions of gait phases were compared with , the value of which is about 1.6180. The ratio between the entire gait cycle and stance phase resulted in 1.620 ± 0.058, that between stance and the swing phase was 1.629 ± 0.173, and that between swing and the double support phase was 1.684 ± 0.357. All these ratios did not differ significantly from each other (, , repeated measure analysis of variance or from (, resp., t-tests. The repetitive gait phases of physiological walking were found in turn in repetitive proportions with each other, revealing an intrinsic harmonic structure. Harmony could be the key for facilitating the control of repetitive walking. Harmony is a powerful unifying factor between seemingly disparate fields of nature, including human gait.

  15. Iconicity in Discourse: The Case of Repetition in Japanese.

    Science.gov (United States)

    Ishikawa, Minako

    This analysis of repeated utterances in Japanese conversational discourse focuses on repetition as an expression of iconicity. In the analysis of a 30-minute conversation among 4 Japanese speakers, the iconic meanings expressed by both reduplication and conversational repetition are highlighted. The iconicity characteristic of conversational data…

  16. Evidence-Based Behavioral Interventions for Repetitive Behaviors in Autism

    Science.gov (United States)

    Boyd, Brian A.; McDonough, Stephen G.; Bodfish, James W.

    2012-01-01

    Restricted and repetitive behaviors (RRBs) are a core symptom of autism spectrum disorders (ASD). There has been an increased research emphasis on repetitive behaviors; however, this research primarily has focused on phenomenology and mechanisms. Thus, the knowledge base on interventions is lagging behind other areas of research. The literature…

  17. Visual attention to advertising : The impact of motivation and repetition

    NARCIS (Netherlands)

    Pieters, RGM; Rosbergen, E; Hartog, M; Corfman, KP; Lynch, JG

    1996-01-01

    Using eye-tracking data, we examine the impact of motivation and repetition on visual attention to advertisements differing in argument quality. Our analyses indicate that repetition leads to an overall decrease in the amount of attention. However, while at first high motivation subjects attend to t

  18. On the Functions of Lexical Repetition in English Texts

    Institute of Scientific and Technical Information of China (English)

    XIAO Fuliang

    2016-01-01

    Lexical repetition, as a cohesive device of an English text, can help make up a cohesive and coherent text. Therefore, in English textual learning, it is helpful for students to know about different patterns and functions of lexical repetition to improve their English level and ability.

  19. Repetitive DNA Sequences in Wheat and Its Relatives

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xue-yong; LI Da-yong

    2001-01-01

    Repetitive DNA sequences form a large portion of eukaryote genomes. Using wheat ( Triticum )as a model, the classification, features and functions of repetitive DNA sequences in the Tritieeae grass tribe is reviewed as well as the role of these sequences in genome differentiation, control and regulation of homologous chromosome synapsis and pairing. Transposable elements, as an important portion of dispersed repetitives,may play an essential role in gene mutation of the host. Dynamic models for change of copy number and sequences of the repetitive family are also presented after the models of Charlesworth et al. Application of repetitive DNA sequences in the study of evolution, chromosome fingerprinting and marker assisted gene transfer and breeding are described by taking wheat as an example.

  20. Nonword Repetition and Speech Motor Control in Children

    Directory of Open Access Journals (Sweden)

    Christina Reuterskiöld

    2015-01-01

    Full Text Available This study examined how familiarity of word structures influenced articulatory control in children and adolescents during repetition of real words (RWs and nonwords (NWs. A passive reflective marker system was used to track articulator movement. Measures of accuracy were obtained during repetition of RWs and NWs, and kinematic analysis of movement duration and variability was conducted. Participants showed greater consonant and vowel accuracy during RW than NW repetition. Jaw movement duration was longer in NWs compared to RWs across age groups, and younger children produced utterances with longer jaw movement duration compared to older children. Jaw movement variability was consistently greater during repetition of NWs than RWs in both groups of participants. The results indicate that increases in phonological short-term memory demands affect articulator movement. This effect is most pronounced in younger children. A range of skills may develop during childhood, which supports NW repetition skills.

  1. Soliton repetition rate in a silicon-nitride microresonator

    CERN Document Server

    Bao, Chengying; Wang, Cong; Jaramillo-Villegas, Jose A; Leaird, Daniel E; Qi, Minghao; Weiner, Andrew M

    2016-01-01

    The repetition rate of a Kerr comb comprising a single soliton in an anomalous dispersion silicon nitride microcavity is measured as a function of pump frequency tuning. The contributions from the Raman soliton self-frequency shift (SSFS) and from thermal effects are evaluated both experimentally and theoretically; the SSFS is found to dominate the changes in repetition rate. The relationship between the changes in repetition rate and pump frequency detuning is found to be independent of the nonlinearity coefficient and dispersion of the cavity. Modeling of the repetition rate change by using the generalized Lugiato-Lefever equation is discussed; the Kerr shock is found to have only a minor effect on repetition rate for cavity solitons with duration down to ~50 fs.

  2. Transgenerational effects of environmental enrichment on repetitive motor behavior development.

    Science.gov (United States)

    Bechard, Allison R; Lewis, Mark H

    2016-07-01

    The favorable consequences of environmental enrichment (EE) on brain and behavior development are well documented. Much less is known, however, about transgenerational benefits of EE on non-enriched offspring. We explored whether transgenerational effects of EE might extend to the development of repetitive motor behaviors in deer mice. Repetitive motor behaviors are invariant patterns of movement that, across species, can be reduced by EE. We found that EE not only attenuated the development of repetitive behavior in dams, but also in their non-enriched offspring. Moreover, maternal behavior did not seem to mediate the transgenerational effect we found, although repetitive behavior was affected by reproductive experience. These data support a beneficial transgenerational effect of EE on repetitive behavior development and suggest a novel benefit of reproductive experience.

  3. Soliton repetition rate in a silicon-nitride microresonator.

    Science.gov (United States)

    Bao, Chengying; Xuan, Yi; Wang, Cong; Jaramillo-Villegas, Jose A; Leaird, Daniel E; Qi, Minghao; Weiner, Andrew M

    2017-02-15

    The repetition rate of a Kerr comb composed of a single soliton in an anomalous group velocity dispersion silicon-nitride microcavity is measured as a function of pump frequency. By comparing operation in the soliton and non-soliton states, the contributions from the Raman soliton self-frequency shift (SSFS) and the thermal effects are evaluated; the SSFS is found to dominate the changes in the repetition rate, similar to silica cavities. The relationship between the changes in the repetition rate and the pump frequency detuning is found to be independent of the nonlinearity coefficient and dispersion of the cavity. Modeling of the repetition rate change by using the generalized Lugiato-Lefever equation is discussed; the Kerr shock is found to have only a minor effect on repetition rate for cavity solitons with duration down to ∼50  fs.

  4. Self-controlled KR schedules: does repetition order matter?

    Science.gov (United States)

    Patterson, Jae T; Carter, Michael J; Hansen, Steve

    2013-08-01

    The impact of an experimenter-defined repetition schedule on the utility of a self-controlled KR context during motor skill acquisition was examined. Participants were required to learn three novel spatial-temporal tasks in either a random or blocked repetition schedule with or without the opportunity to control their KR. Results from the retention period showed that participants provided control over their KR schedule in a random repetition schedule demonstrated superior learning. However, performance measures from the transfer test showed that, independent of repetition schedule, learners provided the opportunity to control their KR schedule demonstrated superior transfer performance compared to their yoked counterparts. The dissociated impact of repetition schedule and self-controlled KR schedules on retention and transfer is discussed.

  5. Impaired speech repetition and left parietal lobe damage.

    Science.gov (United States)

    Fridriksson, Julius; Kjartansson, Olafur; Morgan, Paul S; Hjaltason, Haukur; Magnusdottir, Sigridur; Bonilha, Leonardo; Rorden, Christopher

    2010-08-18

    Patients with left hemisphere damage and concomitant aphasia usually have difficulty repeating others' speech. Although impaired speech repetition, the primary symptom of conduction aphasia, has been associated with involvement of the left arcuate fasciculus, its specific lesion correlate remains elusive. This research examined speech repetition among 45 stroke patients who underwent aphasia testing and MRI examination. Based on lesion-behavior mapping, the primary structural damage most closely associated with impaired speech repetition was found in the posterior portion of the left arcuate fasciculus. However, perfusion-weighted MRI revealed that tissue dysfunction, in the form of either frank damage or hypoperfusion, to the left inferior parietal lobe, rather than the underlying white matter, was associated with impaired speech repetition. This latter result suggests that integrity of the left inferior parietal lobe is important for speech repetition and, as importantly, highlights the importance of examining cerebral perfusion for the purpose of lesion-behavior mapping in acute stroke.

  6. Repetition and Emotive Communication in Music Versus Speech

    Directory of Open Access Journals (Sweden)

    Elizabeth Hellmuth eMargulis

    2013-04-01

    Full Text Available Music and speech are often placed alongside one another as comparative cases. Their relative overlaps and disassociations have been well explored (e.g. Patel, 2010. But one key attribute distinguishing these two domains has often been overlooked: the greater preponderance of repetition in music in comparison to speech. Recent fMRI studies have shown that familiarity – achieved through repetition – is a critical component of emotional engagement with music (Pereira et al., 2011. If repetition is fundamental to emotional responses to music, and repetition is a key distinguisher between the domains of music and speech, then close examination of the phenomenon of repetition might help clarify the ways that music elicits emotion differently than speech.

  7. Physical Characteristics Underpinning Repetitive Lunging in Fencing.

    Science.gov (United States)

    Turner, Anthony N; Marshall, Geoff; Phillips, James; Noto, Angelo; Buttigieg, Conor; Chavda, Shyam; Downing, William; Atlay, Nathan; Dimitriou, Lygeri; Kilduff, Laim

    2016-11-01

    Turner, AN, Marshall, G, Phillips, J, Noto, A, Buttigieg, C, Chavda, S, Downing, W, Atlay, N, Dimitriou, L, and Kilduff, L. Physical characteristics underpinning repetitive lunging in fencing. J Strength Cond Res 30(11): 3134-3139, 2016-Given the repetitive demand to execute lunging and changes in direction within fencing, the ability to sustain these at maximal capacity is fundamental to performance. The aim of this study was threefold. First, to provide normative values for this variable referred to as repeat lunge ability (RLA) and second to identify the physical characteristics that underpin it. Third, was to establish if a cause and effect relationship existed by training the associated characteristics. Assessment of lower-body power, reactive strength, speed, change of direction speed (CODS), and a sport-specific RLA were conducted on senior and junior elite male fencers (n = 36). Fencers were on average (±SD) 18.9 ± 3.2 years of age, 174.35 ± 10.42 cm tall, 70.67 ± 7.35 kg in mass, and 8.5 ± 4.2 years fencing experience. The RLA test had average work times of 16.03 ± 1.40 seconds and demonstrated "large" to "very large" associations with all tested variables, but in particular CODS (r = 0.70) and standing broad jump (SBJ; r = -0.68). Through linear regression analysis, these also provided a 2-predictor model accounting for 61% of the common variance associated with RLA. A cause and effect relationship with SBJ and CODS was confirmed by the training group, where RLA performance in these fencers improved from 15.80 ± 1.07 to 14.90 ± 0.86 seconds, with the magnitude of change reported as "moderate" (effect size (ES) = 0.93). Concurrent improvements were also noted in both SBJ (216.86 ± 17.15 vs. 221.71 ± 17.59 cm) and CODS (4.44 ± 0.29 vs. 4.31 ± 0.09 seconds) and while differences were only significant in SBJ, magnitudes of change were classed as "small" (ES = 0.28) and "moderate" (ES = 0.61), respectively. In conclusion, to improve RLA strength

  8. Generation of low-timing-jitter femtosecond pulse trains with 2 GHz repetition rate via external repetition rate multiplication.

    Science.gov (United States)

    Chen, Jian; Sickler, Jason W; Fendel, Peter; Ippen, Erich P; Kärtner, Franz X; Wilken, Tobias; Holzwarth, Ronald; Hänsch, Theodor W

    2008-05-01

    Generation of low-timing-jitter 150 fs pulse trains at 1560 nm with 2 GHz repetition rate is demonstrated by locking a 200 MHz fundamental polarization additive-pulse mode-locked erbium fiber laser to high-finesse external Fabry-Perot cavities. The timing jitter and relative intensity noise of the repetition-rate multiplied pulse train are investigated.

  9. [Rehabilitation Using Repetitive Transcranial Magnetic Stimulation].

    Science.gov (United States)

    Takeuchi, Naoyuki; Izumi, Shin-Ichi

    2017-03-01

    Various novel stroke rehabilitative methods have been developed based on findings in basic science and clinical research. Recently, many reports have shown that repetitive transcranial magnetic stimulation (rTMS) improves function in stroke patients by altering the excitability of the human cortex. The interhemispheric competition model proposes that deficits in stroke patients are due to reduced output from the affected hemisphere and excessive interhemispheric inhibition from the unaffected hemisphere to the affected hemisphere. The interhemispheric competition model indicates that improvement in deficits can be achieved either by increasing the excitability of the affected hemisphere using excitatory rTMS or by decreasing the excitability of the unaffected hemisphere using inhibitory rTMS. Recovery after stroke is related to neural plasticity, which involves developing new neural connections, acquiring new functions, and compensating for impairments. Artificially modulating the neural network by rTMS may induce a more suitable environment for use-dependent plasticity and also may interfere with maladaptive neural activation, which weakens function and limits recovery. There is potential, therefore, for rTMS to be used as an adjuvant therapy for developed neurorehabilitation techniques in stroke patients.

  10. SI Engine with repetitive NS spark plug

    Science.gov (United States)

    Pancheshniy, Sergey; Nikipelov, Andrey; Anokhin, Eugeny; Starikovskiy, Andrey; Laplase Team; Mipt Team; Pu Team

    2013-09-01

    Now de-facto the only technology for fuel-air mixtures ignition in IC engines exists. It is a spark discharge of millisecond duration in a short discharge gap. The reason for such a small variety of methods of ignition initiation is very specific conditions of the engine operation. First, it is very high-pressure of fuel-air mixture - from 5-7 atmospheres in old-type engines and up to 40-50 atmospheres on the operating mode of HCCI. Second, it is a very wide range of variation of the oxidizer/fuel ratio in the mixture - from almost stoichiometric (0.8-0.9) at full load to very lean (φ = 0.3-0.5) mixtures at idle and/or economical cruising mode. Third, the high velocity of the gas in the combustion chamber (up to 30-50 m/s) resulting in a rapid compression of swirling inlet flow. The paper presents the results of tests of distributed spark ignition system powered by repetitive pulse nanosecond discharge. Dynamic pressure measurements show the increased pressure and frequency stability for nanosecond excitation in comparison with the standard spark plug. Excitation by single nanosecond high-voltage pulse and short train of pulses was examined. In all regimes the nanosecond pulsed excitation demonstrate a better performance.

  11. Repetitive transcranial magnetic stimulation and drug addiction.

    Science.gov (United States)

    Barr, Mera S; Farzan, Faranak; Wing, Victoria C; George, Tony P; Fitzgerald, Paul B; Daskalakis, Zafiris J

    2011-10-01

    Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation technique that is now being tested for its ability to treat addiction. This review discusses current research approaches and results of studies which measured the therapeutic use of rTMS to treat tobacco, alcohol and illicit drug addiction. The research in this area is limited and therefore all studies evaluating the therapeutic use of rTMS in tobacco, alcohol or illicit drug addiction were retained including case studies through NCBI PubMed ( http://www.ncbi.nlm.nih.gov ) and manual searches. A total of eight studies were identified that examined the ability of rTMS to treat tobacco, alcohol and cocaine addiction. The results of this review indicate that rTMS is effective in reducing the level of cravings for smoking, alcohol, and cocaine when applied at high frequencies to the dorsolateral prefrontal cortex (DLPFC). Furthermore, these studies suggest that repeated sessions of high frequency rTMS over the DLPFC may be most effective in reducing the level of smoking and alcohol consumption. Although work in this area is limited, this review indicates that rTMS is a promising modality for treating drug addiction.

  12. Development of a repetitive compact torus injector

    Science.gov (United States)

    Onchi, Takumi; McColl, David; Dreval, Mykola; Rohollahi, Akbar; Xiao, Chijin; Hirose, Akira; Zushi, Hideki

    2013-10-01

    A system for Repetitive Compact Torus Injection (RCTI) has been developed at the University of Saskatchewan. CTI is a promising fuelling technology to directly fuel the core region of tokamak reactors. In addition to fuelling, CTI has also the potential for (a) optimization of density profile and thus bootstrap current and (b) momentum injection. For steady-state reactor operation, RCTI is necessary. The approach to RCTI is to charge a storage capacitor bank with a large capacitance and quickly charge the CT capacitor bank through a stack of integrated-gate bipolar transistors (IGBTs). When the CT bank is fully charged, the IGBT stack will be turned off to isolate banks, and CT formation/acceleration sequence will start. After formation of each CT, the fast bank will be replenished and a new CT will be formed and accelerated. Circuits for the formation and the acceleration in University of Saskatchewan CT Injector (USCTI) have been modified. Three CT shots at 10 Hz or eight shots at 1.7 Hz have been achieved. This work has been sponsored by the CRC and NSERC, Canada.

  13. Repetitive energy transfer from an inductive energy store

    Energy Technology Data Exchange (ETDEWEB)

    Honig, E.M.

    1984-01-01

    The theoretical and experimental results of a research program aimed at finding practical ways to transfer energy repetitively from an inductive energy store to various loads are discussed. The objectives were to investigate and develop the high power opening switches and transfer circuits needed to enable high-repetition-rate operation of such systems, including a feasibility demonstration at a current level near 10 kA and a pulse repetition rate of 1-10 kpps with a 1-ohm load. The requirements of nonlinear, time-varying loads, such as the railgun electromagnetic launcher, were also addressed. Energy storage capability is needed for proper power conditioning in systems where the duty factor of the output pulse train is low. Inductive energy storage is attractive because it has both a high energy storage density and a fast discharge capability. By producing a pulse train with a peak power of 75 MW at a pulse repetition rate of 5 kpps in a one-ohm load system, this research program was the first to demonstrate fully-controlled, high-power, high-repetition-rate operation of an inductive energy storage and transfer system with survivable switches. Success was made possible by using triggered vacuum gap switches as repetitive, current-zero opening switches and developing several new repetitive transfer circuits using the counterpulse technique.

  14. Skill learning in mirror reading: how repetition determines acquisition.

    Science.gov (United States)

    Ofen-Noy, N; Dudai, Y; Karni, A

    2003-07-01

    Practice makes perfect, but the role of repetitions in skill learning is not yet fully understood. For example, given a similar number of trials on a given task, it is debated whether repeating and non-repeating items are learned by the same neural process. When one is given training with both types of items--does one learn two separate skills, or only one? Here we show, using a mirror reading task, that practice trials with trial-unique words, and practice trials with repeated words, count towards learning to a different degree. There was no interaction between the time-course of learning repeated and unique words even within the same individuals given mixed training. While repeated words were learned faster than unique words, the repetitions-dependent gains diminished with training beyond a small number of repetitions. Moreover, the gains in performance could not be accounted for solely by the number of repetitions, as assumed by power-law models of learning; rather, the passage of time was a critical factor. Finally, our results suggest that although both repeated and new words were learned by both declarative and procedural memory mechanisms, even a single repetition of specific words could lead to the establishment of a selective differential representation in memory. The results are compatible with the notion of a repetition-sensitive process, triggered by specific repeating events. This 'repetition counter' may be a critical trigger for the effective formation of procedural as well as some type of declarative memory.

  15. Directed PCR-free engineering of highly repetitive DNA sequences

    Directory of Open Access Journals (Sweden)

    Preissler Steffen

    2011-09-01

    Full Text Available Abstract Background Highly repetitive nucleotide sequences are commonly found in nature e.g. in telomeres, microsatellite DNA, polyadenine (poly(A tails of eukaryotic messenger RNA as well as in several inherited human disorders linked to trinucleotide repeat expansions in the genome. Therefore, studying repetitive sequences is of biological, biotechnological and medical relevance. However, cloning of such repetitive DNA sequences is challenging because specific PCR-based amplification is hampered by the lack of unique primer binding sites resulting in unspecific products. Results For the PCR-free generation of repetitive DNA sequences we used antiparallel oligonucleotides flanked by restriction sites of Type IIS endonucleases. The arrangement of recognition sites allowed for stepwise and seamless elongation of repetitive sequences. This facilitated the assembly of repetitive DNA segments and open reading frames encoding polypeptides with periodic amino acid sequences of any desired length. By this strategy we cloned a series of polyglutamine encoding sequences as well as highly repetitive polyadenine tracts. Such repetitive sequences can be used for diverse biotechnological applications. As an example, the polyglutamine sequences were expressed as His6-SUMO fusion proteins in Escherichia coli cells to study their aggregation behavior in vitro. The His6-SUMO moiety enabled affinity purification of the polyglutamine proteins, increased their solubility, and allowed controlled induction of the aggregation process. We successfully purified the fusions proteins and provide an example for their applicability in filter retardation assays. Conclusion Our seamless cloning strategy is PCR-free and allows the directed and efficient generation of highly repetitive DNA sequences of defined lengths by simple standard cloning procedures.

  16. Repetition-based Interactive Facade Modeling

    KAUST Repository

    AlHalawani, Sawsan

    2012-07-01

    Modeling and reconstruction of urban environments has gained researchers attention throughout the past few years. It spreads in a variety of directions across multiple disciplines such as image processing, computer graphics and computer vision as well as in architecture, geoscience and remote sensing. Having a virtual world of our real cities is very attractive in various directions such as entertainment, engineering, governments among many others. In this thesis, we address the problem of processing a single fa cade image to acquire useful information that can be utilized to manipulate the fa cade and generate variations of fa cade images which can be later used for buildings\\' texturing. Typical fa cade structures exhibit a rectilinear distribution where in windows and other elements are organized in a grid of horizontal and vertical repetitions of similar patterns. In the firt part of this thesis, we propose an efficient algorithm that exploits information obtained from a single image to identify the distribution grid of the dominant elements i.e. windows. This detection method is initially assisted with the user marking the dominant window followed by an automatic process for identifying its repeated instances which are used to define the structure grid. Given the distribution grid, we allow the user to interactively manipulate the fa cade by adding, deleting, resizing or repositioning the windows in order to generate new fa cade structures. Having the utility for the interactive fa cade is very valuable to create fa cade variations and generate new textures for building models. Ultimately, there is a wide range of interesting possibilities of interactions to be explored.

  17. Understanding communicative actions: a repetitive TMS study.

    Science.gov (United States)

    Stolk, Arjen; Noordzij, Matthijs L; Volman, Inge; Verhagen, Lennart; Overeem, Sebastiaan; van Elswijk, Gijs; Bloem, Bas; Hagoort, Peter; Toni, Ivan

    2014-02-01

    Despite the ambiguity inherent in human communication, people are remarkably efficient in establishing mutual understanding. Studying how people communicate in novel settings provides a window into the mechanisms supporting the human competence to rapidly generate and understand novel shared symbols, a fundamental property of human communication. Previous work indicates that the right posterior superior temporal sulcus (pSTS) is involved when people understand the intended meaning of novel communicative actions. Here, we set out to test whether normal functioning of this cerebral structure is required for understanding novel communicative actions using inhibitory low-frequency repetitive transcranial magnetic stimulation (rTMS). A factorial experimental design contrasted two tightly matched stimulation sites (right pSTS vs left MT+, i.e., a contiguous homotopic task-relevant region) and tasks (a communicative task vs a visual tracking task that used the same sequences of stimuli). Overall task performance was not affected by rTMS, whereas changes in task performance over time were disrupted according to TMS site and task combinations. Namely, rTMS over pSTS led to a diminished ability to improve action understanding on the basis of recent communicative history, while rTMS over MT+ perturbed improvement in visual tracking over trials. These findings qualify the contributions of the right pSTS to human communicative abilities, showing that this region might be necessary for incorporating previous knowledge, accumulated during interactions with a communicative partner, to constrain the inferential process that leads to action understanding. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Epithelial topography for repetitive tooth formation

    Directory of Open Access Journals (Sweden)

    Marcia Gaete

    2015-12-01

    Full Text Available During the formation of repetitive ectodermally derived organs such as mammary glands, lateral line and teeth, the tissue primordium iteratively initiates new structures. In the case of successional molar development, new teeth appear sequentially in the posterior region of the jaw from Sox2+ cells in association with the posterior aspect of a pre-existing tooth. The sequence of molar development is well known, however, the epithelial topography involved in the formation of a new tooth is unclear. Here, we have examined the morphology of the molar dental epithelium and its development at different stages in the mouse in vivo and in molar explants. Using regional lineage tracing we show that within the posterior tail of the first molar the primordium for the second and third molar are organized in a row, with the tail remaining in connection with the surface, where a furrow is observed. The morphology and Sox2 expression of the tail retains characteristics reminiscent of the earlier stages of tooth development, such that position along the A-P axes of the tail correlates with different temporal stages. Sox9, a stem/progenitor cell marker in other organs, is expressed mainly in the suprabasal epithelium complementary with Sox2 expression. This Sox2 and Sox9 expressing molar tail contains actively proliferating cells with mitosis following an apico-basal direction. Snail2, a transcription factor implicated in cell migration, is expressed at high levels in the tip of the molar tail while E-cadherin and laminin are decreased. In conclusion, our studies propose a model in which the epithelium of the molar tail can grow by posterior movement of epithelial cells followed by infolding and stratification involving a population of Sox2+/Sox9+ cells.

  19. Repetitive transcranial magnetic stimulation in psychiatry

    Directory of Open Access Journals (Sweden)

    Biswa Ranjan Mishra

    2011-01-01

    Full Text Available Repetitive transcranial magnetic stimulation (rTMS is a non-invasive and relatively painless tool that has been used to study various cognitive functions as well as to understand the brain-behavior relationship in normal individuals as well as in those with various neuropsychiatric disorders. It has also been used as a therapeutic tool in various neuropsychiatric disorders because of its ability to specifically modulate distinct brain areas. Studies have shown that repeated stimulation at low frequency produces long-lasting inhibition, which is called as long-term depression, whereas repeated high-frequency stimulation can produce excitation through long-term potentiation. This paper reviews the current status of rTMS as an investigative and therapeutic modality in various neuropsychiatric disorders. It has been used to study the cortical and subcortical functions, neural plasticity and brain mapping in normal individuals and in various neuropsychiatric disorders. rTMS has been most promising in the treatment of depression, with an overall milder adverse effect profile compared with electroconvulsive therapy. In other neuropsychiatric disorders such as schizophrenia, mania, epilepsy and substance abuse, it has been found to be useful, although further studies are required to establish therapeutic efficacy. It appears to be ineffective in the treatment of obsessive compulsive disorder. There is a paucity of studies of efficacy and safety of rTMS in pediatric and geriatric population. Although it appears safe, further research is required to optimize its efficacy and reduce the side-effects. Magnetic seizure therapy, which involves producing seizures akin to electroconvulsive therapy, appears to be of comparable efficacy in the treatment of depression with less cognitive adverse effects.

  20. Clinical application of repetitive transcranial magnetic stimulation in stroke rehabilitation☆

    Science.gov (United States)

    Shin, Joonho; Yang, EunJoo; Cho, KyeHee; Barcenas, Carmelo L; Kim, Woo Jin; Min, Yusun; Paik, Nam-Jong

    2012-01-01

    Proper stimulation to affected cerebral hemisphere would promote the functional recovery of patients with stroke. Effects of repetitive transcranial magnetic stimulation on cortical excitability can be can be altered by the stimulation frequency, intensity and duration. There has been no consistent recognition regarding the best stimulation frequency and intensity. This study reviews the intervention effects of repetitive transcranial stimulation on motor impairment, dysphagia, visuospatial neglect and aphasia, and summarizes the stimulation frequency, intensity and area for repetitive transcranial magnetic stimulation to yield the best therapeutic effects. PMID:25745455

  1. Clinical application of repetitive transcranial magnetic stimulation in stroke rehabilitation

    Institute of Scientific and Technical Information of China (English)

    Joonho Shin; EunJoo Yang; KyeHee Cho; Carmelo L Barcenas; Woo Jin Kim; Yusun Min; Nam-Jong Paik

    2012-01-01

    Proper stimulation to affected cerebral hemisphere would promote the functional recovery of patients with stroke. Effects of repetitive transcranial magnetic stimulation on cortical excitability can be can be altered by the stimulation frequency, intensity and duration. There has been no consistent recognition regarding the best stimulation frequency and intensity. This study reviews the intervention effects of repetitive transcranial stimulation on motor impairment, dysphagia, visuospatial neglect and aphasia, and summarizes the stimulation frequency, intensity and area for repetitive transcranial magnetic stimulation to yield the best therapeutic effects.

  2. Shortening of subjective visual intervals followed by repetitive stimulation.

    Directory of Open Access Journals (Sweden)

    Fuminori Ono

    Full Text Available Our previous research demonstrated that repetitive tone stimulation shortened the perceived duration of the preceding auditory time interval. In this study, we examined whether repetitive visual stimulation influences the perception of preceding visual time intervals. Results showed that a time interval followed by a high-frequency visual flicker was perceived as shorter than that followed by a low-frequency visual flicker. The perceived duration decreased as the frequency of the visual flicker increased. The visual flicker presented in one hemifield shortened the apparent time interval in the other hemifield. A final experiment showed that repetitive tone stimulation also shortened the perceived duration of preceding visual time intervals. We concluded that visual flicker shortened the perceived duration of preceding visual time intervals in the same way as repetitive auditory stimulation shortened the subjective duration of preceding tones.

  3. The relationship between task repetition and language proficiency

    Directory of Open Access Journals (Sweden)

    Ahmad Mojavezi

    2014-01-01

    Full Text Available Task repetition is now considered as an important task-based implementation variable which can affect complexity, accuracy, and fluency of L2 speech. However, in order to move towards theorizing the role of task repetition in second language acquisition, it is necessary that individual variables be taken into account. The present study aimed to investigate the way task repetition correlates with language proficiency and the differential effects that task repetition might have on the complexity, accuracy, and fluency of L2 learners with different levels of proficiency. Fifty language learners of different levels of proficiency, selected from two different language centers, participated in this study. They were asked to perform an oral narrative task twice with a one-week interval. Results revealed that, compared to the participants with lower L2 proficiency, participants with higher levels of L2 proficiency produced more complex, accurate, and fluent speech on the second encounter with the same task.

  4. The repetition effect in building and construction works

    DEFF Research Database (Denmark)

    Gottlieb, Stefan Christoffer; Haugbølle, Kim

    are then applied on the Public Transport Authorities' main account structure of units and costs, and a method for assessing the possibilities of achieving effects of repetition for each account is described. Finally, the report summarises the core conditions necessary to take into consideration in relation......This report summarises the results from the work undertaken for the Public Transport Authority on the effect of learning and repetition in building and construction works. The results are applied by the Public Transport Authority in a new budgeting model, while the agency investigates...... the establishment of a new railway between Copenhagen and Ringsted. Drawing on an extensive literature review, the effect of repetition is determined to be in the range of 6-12 %. Further, the report identifies a series of factors affecting the possibilities of achieving effects of repetition. These factors...

  5. Neural dynamics during repetitive visual stimulation

    Science.gov (United States)

    Tsoneva, Tsvetomira; Garcia-Molina, Gary; Desain, Peter

    2015-12-01

    Objective. Steady-state visual evoked potentials (SSVEPs), the brain responses to repetitive visual stimulation (RVS), are widely utilized in neuroscience. Their high signal-to-noise ratio and ability to entrain oscillatory brain activity are beneficial for their applications in brain-computer interfaces, investigation of neural processes underlying brain rhythmic activity (steady-state topography) and probing the causal role of brain rhythms in cognition and emotion. This paper aims at analyzing the space and time EEG dynamics in response to RVS at the frequency of stimulation and ongoing rhythms in the delta, theta, alpha, beta, and gamma bands. Approach.We used electroencephalography (EEG) to study the oscillatory brain dynamics during RVS at 10 frequencies in the gamma band (40-60 Hz). We collected an extensive EEG data set from 32 participants and analyzed the RVS evoked and induced responses in the time-frequency domain. Main results. Stable SSVEP over parieto-occipital sites was observed at each of the fundamental frequencies and their harmonics and sub-harmonics. Both the strength and the spatial propagation of the SSVEP response seem sensitive to stimulus frequency. The SSVEP was more localized around the parieto-occipital sites for higher frequencies (>54 Hz) and spread to fronto-central locations for lower frequencies. We observed a strong negative correlation between stimulation frequency and relative power change at that frequency, the first harmonic and the sub-harmonic components over occipital sites. Interestingly, over parietal sites for sub-harmonics a positive correlation of relative power change and stimulation frequency was found. A number of distinct patterns in delta (1-4 Hz), theta (4-8 Hz), alpha (8-12 Hz) and beta (15-30 Hz) bands were also observed. The transient response, from 0 to about 300 ms after stimulation onset, was accompanied by increase in delta and theta power over fronto-central and occipital sites, which returned to baseline

  6. Autism and exergaming: effects on repetitive behaviors and cognition

    OpenAIRE

    Anderson-Hanley C; Tureck K; Schneiderman RL

    2011-01-01

    Cay Anderson-Hanley, Kimberly Tureck, Robyn L Schneiderman Department of Psychology, Union College, Schenectady, NY, USA Abstract: Autism is a neurodevelopmental disorder that leads to impairment in social skills and delay in language development, and results in repetitive behaviors and restricted interests that impede academic and social involvement. Physical exercise has been shown to decrease repetitive behaviors in autistic children and improve cognitive function across the life-span. Ex...

  7. Breakdown behavior of electronics at variable pulse repetition rates

    OpenAIRE

    Korte, S.; H. Garbe

    2006-01-01

    The breakdown behavior of electronics exposed to single transient electromagnetic pulses is subject of investigations for several years. State-of-the-art pulse generators additionally provide the possibility to generate pulse sequences with variable pulse repetition rate. In this article the influence of this repetition rate variation on the breakdown behavior of electronic systems is described. For this purpose microcontroller systems are examined during line-led exposure to pulses with repe...

  8. Analysis of repetitive DNA in chromosomes by flow cytometry.

    Science.gov (United States)

    Brind'Amour, Julie; Lansdorp, Peter M

    2011-06-01

    We developed a flow cytometry method, chromosome flow fluorescence in situ hybridization (FISH), called CFF, to analyze repetitive DNA in chromosomes using FISH with directly labeled peptide nucleic acid (PNA) probes. We used CFF to measure the abundance of interstitial telomeric sequences in Chinese hamster chromosomes and major satellite sequences in mouse chromosomes. Using CFF we also identified parental homologs of human chromosome 18 with different amounts of repetitive DNA.

  9. Linear- and Repetitive-Feature Detection Within Remotely Sensed Imagery

    Science.gov (United States)

    2017-04-01

    1.1 Background The Army desires the ability to deliver cargo, equipment, and personnel to harsh locations almost anywhere on the planet . This...because the Hough transform is designed to look for straight linear features, which most real- life fea- tures are not. As mention previously, it is...repetitive features are differentiated based on their appearance in the images of interest; however, real- life repetitive features often corre- spond to

  10. Linear- and Repetitive Feature Detection Within Remotely Sensed Imagery

    Science.gov (United States)

    2017-04-01

    1.1 Background The Army desires the ability to deliver cargo, equipment, and personnel to harsh locations almost anywhere on the planet . This...because the Hough transform is designed to look for straight linear features, which most real- life fea- tures are not. As mention previously, it is...repetitive features are differentiated based on their appearance in the images of interest; however, real- life repetitive features often corre- spond to

  11. Brain Injury Following Repetitive Apnea in Newborn Piglets

    Science.gov (United States)

    Schears, Gregory; Creed, Jennifer; Antoni, Diego; Zaitseva, Tatiana; Greeley, William; Wilson, David F.; Pastuszko, Anna

    Repetitive apnea is associated with a significant increase in extracellular dopamine, generation of free radicals as determined by o-tyrosine formation and increase in Fluoro-Jade staining of degenerating neurons. This increase in extracellular dopamine and of hydroxyl radicals in striatum of newborn brain is likely to be at least partly responsible for the neuronal injury and neurological side effects of repetitive apnea.

  12. Illusory sensation of movement induced by repetitive transcranial magnetic stimulation

    DEFF Research Database (Denmark)

    Christensen, Mark Schram; Lundbye-Jensen, J.; Grey, M.J.;

    2010-01-01

    Human movement sense relies on both somatosensory feedback and on knowledge of the motor commands used to produce the movement. We have induced a movement illusion using repetitive transcranial magnetic stimulation over primary motor cortex and dorsal premotor cortex in the absence of limb moveme...... premotor cortex stimulation was less affected by sensory and motor deprivation than was primary motor cortex stimulation. We propose that repetitive transcranial magnetic stimulation over dorsal premotor cortex produces a corollary discharge that is perceived as movement....

  13. Grade repetition in primary school from teachers’ perspective

    Directory of Open Access Journals (Sweden)

    Malinić Dušica

    2011-01-01

    Full Text Available School underachievement is exhibited gradually, in different forms, while grade repetition figures as one of the most prominent forms of underachievement. In order to observe this phenomenon from different perspectives, we conducted a research aimed at identifying teacher attitudes towards grade repetition and grade repeaters in primary school, based on their perceptions of: (a the cause of grade repetition; (b the responsibility for grade repetition and (c grade repetition as an educational measure. The administered questionnaire was constructed for the purposes of the research, descriptive statistics was used, and data were obtained on the sample of 136 teachers from 31 primary schools from the territory of the City of Belgrade. The results point out to the conclusion that teachers perceive grade repetition as, first and foremost, the consequence of students’ lack of interest in school and learning and undisciplined behavior in class. By treating student underachievement mainly as a consequence of laziness, lack of motivation and insufficient effort, teachers transfer responsibility to others, assessing that the personal degree of responsibility for the underachievement of their students is very low. The responsibility for underachievement is perceived more as a problem of the student, his/her family, peer group, than as the problem of teachers themselves. The concluding part points out to certain teaching procedures and methods that have proved to be useful in the prevention of student underachievement.

  14. Properties of water surface discharge at different pulse repetition rates

    Energy Technology Data Exchange (ETDEWEB)

    Ruma,; Yoshihara, K. [Graduate School of Science and Technology, Kumamoto University, Kumamoto 860-8555 (Japan); Hosseini, S. H. R., E-mail: hosseini@kumamoto-u.ac.jp; Sakugawa, T.; Akiyama, H. [Graduate School of Science and Technology, Kumamoto University, Kumamoto 860-8555 (Japan); Institute of Pulsed Power Science, Kumamoto University, Kumamoto 860-8555 (Japan); Akiyama, M. [Department of Electrical and Electronic Engineering, Kagoshima University, Kagoshima 890-0065 (Japan); Lukeš, P. [Institute of Plasma Physics, AS CR, Prague, Prague 18200 (Czech Republic)

    2014-09-28

    The properties of water surface discharge plasma for variety of pulse repetition rates are investigated. A magnetic pulse compression (MPC) pulsed power modulator able to deliver pulse repetition rates up to 1000 Hz, with 0.5 J per pulse energy output at 25 kV, was used as the pulsed power source. Positive pulse with a point-to-plane electrode configuration was used for the experiments. The concentration and production yield of hydrogen peroxide (H₂O₂) were quantitatively measured and orange II organic dye was treated, to evaluate the chemical properties of the discharge reactor. Experimental results show that the physical and chemical properties of water surface discharge are not influenced by pulse repetition rate, very different from those observed for under water discharge. The production yield of H₂O₂ and degradation rate per pulse of the dye did not significantly vary at different pulse repetition rates under a constant discharge mode on water surface. In addition, the solution temperature, pH, and conductivity for both water surface and underwater discharge reactors were measured to compare their plasma properties for different pulse repetition rates. The results confirm that surface discharge can be employed at high pulse repetition rates as a reliable and advantageous method for industrial and environmental decontamination applications.

  15. Place field repetition and spatial learning in a multicompartment environment.

    Science.gov (United States)

    Grieves, Roddy M; Jenkins, Bryan W; Harland, Bruce C; Wood, Emma R; Dudchenko, Paul A

    2016-01-01

    Recent studies have shown that place cells in the hippocampus possess firing fields that repeat in physically similar, parallel environments. These results imply that it should be difficult for animals to distinguish parallel environments at a behavioral level. To test this, we trained rats on a novel odor-location task in an environment with four parallel compartments which had previously been shown to yield place field repetition. A second group of animals was trained on the same task, but with the compartments arranged in different directions, an arrangement we hypothesised would yield less place field repetition. Learning of the odor-location task in the parallel compartments was significantly impaired relative to learning in the radially arranged compartments. Fewer animals acquired the full discrimination in the parallel compartments compared to those trained in the radial compartments, and the former also required many more sessions to reach criterion compared to the latter. To confirm that the arrangement of compartments yielded differences in place cell repetition, in a separate group of animals we recorded from CA1 place cells in both environments. We found that CA1 place cells exhibited repeated fields across four parallel local compartments, but did not do so when the same compartments were arranged radially. To confirm that the differences in place field repetition across the parallel and radial compartments depended on their angular arrangement, and not incidental differences in access to an extra-maze visual landmark, we repeated the recordings in a second set of rats in the absence of the orientation landmark. We found, once again, that place fields showed repetition in parallel compartments, and did not do so in radially arranged compartments. Thus place field repetition, or lack thereof, in these compartments was not dependent on extra-maze cues. Together, these results imply that place field repetition constrains spatial learning.

  16. RPERT: Repetitive-Projects Evaluation and Review Technique

    Directory of Open Access Journals (Sweden)

    Remon Fayek Aziz

    2014-03-01

    Full Text Available Estimating expected completion probability of any repetitive construction project with a specified/certain duration including repetitive identical activities by using program evaluation and review technique is the most essential part in construction areas since the activities were had optimistic, most likely and pessimistic durations. This paper focuses on the calculation of expected completion probability of any repetitive construction project within a specified/certain duration (contract duration by using Line Of Balance technique (LOB in case of single or multiple number of crews integrated with Program Evaluation and Review Technique (PERT. Repetitive-Projects Evaluation and Review Technique (RPERT, which is a simplified software, will generate the expected project completion probability of a specified/certain duration (contract duration. RPERT software is designed by java programming code system to provide a number of new and unique capabilities, including: (1 Viewing the expected project completion probability according to a set of specified durations per each identical activity (optimistic time, most likely time, and pessimistic time in the analyzed project; (2 Providing seamless integration with available project time calculations. In order to provide the aforementioned capabilities of RPERT, the system is implemented and developed in four main modules: (1 A user interface module; (2 A database module; (3 A running module; and (4 A processing module. At the end, an illustrative example will be presented to demonstrate and verify the applications of proposed software (RPERT, by using probabilistic calculations for repetitive construction projects.

  17. Autism and exergaming: effects on repetitive behaviors and cognition

    Directory of Open Access Journals (Sweden)

    Anderson-Hanley C

    2011-09-01

    Full Text Available Cay Anderson-Hanley, Kimberly Tureck, Robyn L Schneiderman Department of Psychology, Union College, Schenectady, NY, USA Abstract: Autism is a neurodevelopmental disorder that leads to impairment in social skills and delay in language development, and results in repetitive behaviors and restricted interests that impede academic and social involvement. Physical exercise has been shown to decrease repetitive behaviors in autistic children and improve cognitive function across the life-span. Exergaming combines physical and mental exercise simultaneously by linking physical activity movements to video game control and may yield better compliance with exercise. In this investigation, two pilot studies explored the potential behavioral and cognitive benefits of exergaming. In Pilot I, twelve children with autism spectrum disorders completed a control task and an acute bout of Dance Dance Revolution (DDR; in Pilot II, ten additional youths completed an acute bout of cyber cycling. Repetitive behaviors and executive function were measured before and after each activity. Repetitive behaviors significantly decreased, while performance on Digits Backwards improved following the exergaming conditions compared with the control condition. Additional research is needed to replicate these findings, and to explore the application of exergaming for the management of behavioral disturbance and to increase cognitive control in children on the autism spectrum. Keywords: autism, repetitive behaviors, exergaming, exercise, executive function

  18. Quantifying repetitive speech in autism spectrum disorders and language impairment.

    Science.gov (United States)

    van Santen, Jan P H; Sproat, Richard W; Hill, Alison Presmanes

    2013-10-01

    We report on an automatic technique for quantifying two types of repetitive speech: repetitions of what the child says him/herself (self-repeats) and of what is uttered by an interlocutor (echolalia). We apply this technique to a sample of 111 children between the ages of four and eight: 42 typically developing children (TD), 19 children with specific language impairment (SLI), 25 children with autism spectrum disorders (ASD) plus language impairment (ALI), and 25 children with ASD with normal, non-impaired language (ALN). The results indicate robust differences in echolalia between the TD and ASD groups as a whole (ALN + ALI), and between TD and ALN children. There were no significant differences between ALI and SLI children for echolalia or self-repetitions. The results confirm previous findings that children with ASD repeat the language of others more than other populations of children. On the other hand, self-repetition does not appear to be significantly more frequent in ASD, nor does it matter whether the child's echolalia occurred within one (immediate) or two turns (near-immediate) of the adult's original utterance. Furthermore, non-significant differences between ALN and SLI, between TD and SLI, and between ALI and TD are suggestive that echolalia may not be specific to ALN or to ASD in general. One important innovation of this work is an objective fully automatic technique for assessing the amount of repetition in a transcript of a child's utterances.

  19. ROBUST REPETITIVE CONTROL FOR IMPROVING RATE SMOOTHNESS OF TEST TURNTABLE

    Institute of Scientific and Technical Information of China (English)

    LIUYu; ZENGMing; SUBao-ku

    2005-01-01

    A robust repetitive control scheme is used to improve the rate smoothness of a brushless DC motor (BLDCM) driven test turntable. The method synthesizes variable structure control (VSC) laws and repetitive control (RC) laws in a complementary manner. The VSC strategy can stabilize the system and suppress uncertainties, such as the aperiodic disturbance and noises, while RC strategy can eliminate the periodic rate fluctuation in a steady state. The convergence of the repetitive learning process is also guaranteed by VSC. A general nonlinear system model is discussed. The model can be considered as an extension of BLDCMs. The stability and asymptotic position tracking performance are validated by using Lyapunov functions. Simulation results show the effectiveness of the proposed approach for improving the rate smoothness.

  20. Body-focused repetitive behavior disorders in ICD-11

    Directory of Open Access Journals (Sweden)

    Jon E. Grant

    2014-01-01

    Full Text Available This article addresses the question of how body-focused repetitive behavior disorders (e.g., trichotillomania and skin-picking disorder should be characterized in ICD-11. The article reviews the historical nosology of the two disorders and the current approaches in DSM-5 and ICD-10. Although data are limited and mixed regarding the optimal relationship between body-focused repetitive behavior disorders and nosological categories, these conditions should be included within the obsessive-compulsive and related disorders category, as this is how most clinicians see these behaviors, and as this may optimize clinical utility. The descriptions of these disorders should largely mirror those in DSM-5, given the evidence from recent field surveys. The recommendations regarding ICD-11 and body-focused repetitive behavior disorders should promote the global identification and treatment of these conditions in primary care settings.

  1. Repeated text in unrelated passages: Repetition versus meaning selection effects.

    Science.gov (United States)

    Klin, Celia M; Drumm, April M; Ralano, Angela S

    2009-07-01

    Despite previous findings, Klin, Ralano, and Weingartner (2007) found transfer benefits across unrelated passages. After processing an ambiguous phrase in Story A that was biased toward its sarcastic meaning, readers were more likely to interpret the identical phrase in Story B as sarcastic, even though it contained no disambiguating information. In the present experiments, we found both repetition effects (a benefit for the lexical items) and meaning selection effects (a benefit for the selected meaning of the phrase) with short delays between Stories A and B; with longer delays, only repetition effects were found. Whereas decreasing the elaboration of the phrase eliminated both effects, moving the disambiguating context from before to after the phrase eliminated meaning selection effects only. We conclude that meaning selection effects, which are based on conceptual overlap, are more sensitive to context changes and less robust than repetition effects, which are based on both perceptual and conceptual overlap.

  2. Effects of repetition and temperature on Contingent Electrical Stimulation

    DEFF Research Database (Denmark)

    Castrillon, Eduardo E.; Zhou, Xinwen; Svensson, Peter

    Effects of repetition and temperature on Contingent Electrical Stimulation. E.E. Castrillon W1, 2, Xinwen Zhou 3, P. Svensson1, 2, 4 1 Department of Dentistry and Oral Health, Section of Orofacial Pain and Jaw Function, Aarhus University, Denmark2 Scandinavian Center for Orofacial Neuroscience...... (SCON)3 Department of Dentistry, Beijing Shijitan Hospital, Capital Medical University, Beijing, China. 4 Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden  Background: Contingent electrical stimulation (CES) of the facial skin has been shown to reduce electromyographic (EMG......) activity associated with bruxism. Repetition of the electrical stimulus and skin surface temperature (ST) may affect the perception of CES and possibly also the inhibitory EMG effects.Objectives: To determine the effects of stimulus repetition and skin ST on the perception of CES.  Methods: Healthy...

  3. Restricted Repetitive Sampling in Designing of Control Charts

    Directory of Open Access Journals (Sweden)

    Muhammad Anwar Mughal

    2017-06-01

    Full Text Available In this article a criteria have been defined to classify the existing repetitive sampling into soft, moderate and strict conditions. Behind this division a ratio has been suggested i.e. c2 (constant used in repetitive limits to c1(constant used in control limit in slabs. A restricted criterion has been devised on the existing repetitive sampling. By embedding the proposed schematic in the control chart it becomes highly efficient in detecting the shifts quite earlier as well as it detects even smaller shifts at smaller ARLs. To facilitate the user for best choice the restricted criterion has further categorized to softly restricted, moderately restricted and strictly restricted. The restricted conditions are dependent on value of restriction parameter ’m’ varies 2 to 6. The application of proposed scheme on selected cases is given in tables which are self explanatory.

  4. Oral Language Skills Moderate Nonword Repetition Skills in Children with Dyslexia: A Meta-Analysis of the Role of Nonword Repetition Skills in Dyslexia

    Science.gov (United States)

    Melby-Lervag, Monica; Lervag, Arne

    2012-01-01

    We present a meta-analysis reviewing studies that have focused on the relationship between dyslexia and nonword repetition. The results show that children with dyslexia have poorer nonword repetition skills when compared to both chronological-age and reading-level controls. However, the severity of the nonword repetition problem varies…

  5. Oral Language Skills Moderate Nonword Repetition Skills in Children with Dyslexia: A Meta-Analysis of the Role of Nonword Repetition Skills in Dyslexia

    Science.gov (United States)

    Melby-Lervag, Monica; Lervag, Arne

    2012-01-01

    We present a meta-analysis reviewing studies that have focused on the relationship between dyslexia and nonword repetition. The results show that children with dyslexia have poorer nonword repetition skills when compared to both chronological-age and reading-level controls. However, the severity of the nonword repetition problem varies…

  6. Effect of repetitive mckenzie lumbar spine exercises on cardiovascular system

    Directory of Open Access Journals (Sweden)

    Agrawal Sonal S

    2014-07-01

    Full Text Available Background & Purpose: McKenzie exercises for the lumbar spine, which are done repeatedly, such as flexion in standing (FIS, extension in standing flexion in lying (FIL & extension in lying (EIL have been used in the management of low back pain for over three decades. The cardiovascular effects of exercises that involve postural stabilization, arm exercises and of exercises performed in lying are well known, but there are seldom studies performed to assess the cardiovascular effects of these commonly used McKenzie exercises. Therefore the study focused on evaluating the effects of 4 commonly used McKenzie exercises on the cardiovascular system. Methods: 80 subjects in the age group of 20-59 years were randomly assigned into 4 groups according to their age, such that such that each group comprised of an equal number of subjects & equal number of males & females. Each subject performed all the 4 exercises (FIS, EIS, FIL & EIL for 10, 15 & 20 repetitions respectively. Heart rate, blood pressure & rate pressure product were recorded before & after each set of repetitions & after each type of exercise. Results: Repetitive McKenzie lumbar spine exercises had cardiovascular effects in apparently healthy subjects (both male & female. Exercises performed in lying were hemodynamically more demanding than that performed in standing, also exercises involving flexion of the lumbar spine elicited greater cardiovascular demand as compared to extension exercises i.e. FIL>EIL>FIS>EIS irrespective of the number of repetitions, 10, 15 or 20. The cardiovascular demand for a given subject increased as the number of repetitions increased, for all the 4 exercises. Conclusion: McKenzie exercises when done repetitively have cardiovascular effects in healthy subjects.

  7. The neural correlates of picture naming facilitated by auditory repetition

    Directory of Open Access Journals (Sweden)

    Heath Shiree

    2012-02-01

    Full Text Available Abstract Background Overt repetition of auditorily presented words can facilitate picture naming performance in both unimpaired speakers and individuals with word retrieval difficulties, but the underlying neurocognitive mechanisms and longevity of such effects remain unclear. This study used functional magnetic resonance imaging to examine whether different neurological mechanisms underlie short-term (within minutes and long-term (within days facilitation effects from an auditory repetition task in healthy older adults. Results The behavioral results showed that both short- and long-term facilitated items were named significantly faster than unfacilitated items, with short-term items significantly faster than long-term items. Neuroimaging analyses identified a repetition suppression effect for long-term facilitated items, relative to short-term facilitated and unfacilitated items, in regions known to be associated with both semantic and phonological processing. A repetition suppression effect was also observed for short-term facilitated items when compared to unfacilitated items in a region of the inferior temporal lobe linked to semantic processing and object recognition, and a repetition enhancement effect when compared to long-term facilitated items in a posterior superior temporal region associated with phonological processing. Conclusions These findings suggest that different neurocognitive mechanisms underlie short- and long-term facilitation of picture naming by an auditory repetition task, reflecting both phonological and semantic processing. More specifically, the brain areas engaged were consistent with the view that long-term facilitation may be driven by a strengthening of semantic-phonological connections. Short-term facilitation, however, appears to result in more efficient semantic processing and/or object recognition, possibly in conjunction with active recognition of the phonological form.

  8. Frobenius morphisms and stable module categories of repetitive algebras

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Let k be the algebraic closure of a finite field F_q and A be a finite dimensional k-algebra with a Frobenius morphism F.In the present paper we establish a relation between the stable module category of the repetitive algebra  of A and that of the repetitive algebra of the fixed-point algebra A~F.As an application,it is shown that the derived category of A~F is equivalent to the subcategory of F-stable objects in the derived category of A when A has a finite global dimension.

  9. Risk factors for hand-wrist disorders in repetitive work

    DEFF Research Database (Denmark)

    Thomsen, J. F.; Mikkelsen, S.; Andersen, JH

    2007-01-01

    (wrist pain and palpation tenderness) were determined in 3123 employees in 19 industrial settings. With the use of questionnaires and video recordings of homogenous work tasks number of wrist movements, hand force requirements and wrist position were analysed as risk factors for hand-wrist disorders......OBJECTIVES: To identify the risk of hand-wrist disorders related to repetitive movements, use of hand force and wrist position in repetitive monotonous work. METHODS: Using questionnaires and physical examinations, the prevalence and incidence of hand-wrist pain and possible extensor tendonitis...... were less consistent. Working with the hand in a non-neutral position could not be identified as a risk factor...

  10. Demonstration of a high repetition rate capillary discharge waveguide

    Energy Technology Data Exchange (ETDEWEB)

    Gonsalves, A. J., E-mail: ajgonsalves@lbl.gov; Pieronek, C.; Daniels, J.; Bulanov, S. S.; Waldron, W. L.; Mittelberger, D. E.; Leemans, W. P. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Liu, F.; Antipov, S.; Butler, J. E. [Euclid TechLabs, Gaithersburg, Maryland 20879 (United States); Bobrova, N. A.; Sasorov, P. V. [Keldysh Institute of Applied Mathematics, Moscow (Russian Federation)

    2016-01-21

    A hydrogen-filled capillary discharge waveguide operating at kHz repetition rates is presented for parameters relevant to laser plasma acceleration (LPA). The discharge current pulse was optimized for erosion mitigation with laser guiding experiments and MHD simulation. Heat flow simulations and measurements showed modest temperature rise at the capillary wall due to the average heat load at kHz repetition rates with water-cooled capillaries, which is promising for applications of LPAs such as high average power radiation sources.

  11. Medium Repetition Rate TEA Laser For Industrial Applications

    Science.gov (United States)

    Walter, Bruno

    1987-09-01

    The design and performance of an inexpensive compact repetitively pulsed TEA CO2 laser is described. The device uses a modified corona preionization technique and a fast transverse gas flow to achieve high repetition rates. An output energy of 500 mJ per pulse and an out-put power of 6.2W at 40Hz have been obtained. Due to the small energy needed for preionization, the efficiency of the device is high, whereas the gas dissociation is low when compared with commercial laser systems. This results in the relatively small fresh laser gas exchange of 20 ltr h-1 for long term operation.

  12. A mouse model of human repetitive mild traumatic brain injury

    OpenAIRE

    Kane, Michael J; Pérez, Mariana Angoa; Briggs, Denise I.; Viano, David C.; Kreipke, Christian W.; Kuhn, Donald M.

    2011-01-01

    A novel method for the study of repetitive mild traumatic brain injury (rmTBI) that models the most common form of head injury in humans is presented. Existing animal models of TBI impart focal, severe damage unlike that seen in repeated and mild concussive injuries, and few are configured for repetitive application. Our model is a modification of the Marmarou weight drop method and allows repeated head impacts to lightly anesthetized mice. A key facet of this method is the delivery of an imp...

  13. Convention, Repetition and Abjection: The Way of the Gothic

    OpenAIRE

    Łowczanin Agnieszka

    2014-01-01

    This paper employs Deleuze and Kristeva in an examination of certain Gothic conventions. It argues that repetition of these conventions- which endows Gothicism with formulaic coherence and consistence but might also lead to predictability and stylistic deadlock-is leavened by a novelty that Deleuze would categorize as literary “gift.” This particular kind of “gift” reveals itself in the fiction of successive Gothic writers on the level of plot and is applied to the repetition of the genre’s m...

  14. Urine concentrations of repetitive doses of inhaled salbutamol

    DEFF Research Database (Denmark)

    Elers, J; Pedersen, Lars; Henninge, J;

    2011-01-01

    We examined blood and urine concentrations of repetitive doses of inhaled salbutamol in relation to the existing cut-off value used in routine doping control. We compared the concentrations in asthmatics with regular use of beta2-agonists prior to study and healthy controls with no previous use...... of beta2-agonists. We enrolled 10 asthmatics and 10 controls in an open-label study in which subjects inhaled repetitive doses of 400 microgram salbutamol every second hour (total 1600 microgram), which is the permitted daily dose by the World Anti-Doping Agency (WADA). Blood samples were collected...

  15. A Brief Account on the Functions of Rhetorical Repetition

    Institute of Scientific and Technical Information of China (English)

    Li Yuping

    2000-01-01

    It is believed that using rhetoric devices precisely is of great importance for the English Learners, if they want to write good articles. Repetition is one of the rhetoric devices that is frequently used in English writing. This paper gives a brief account on the four functions of repetition by presenting some typical examples, focusing the reader's attention on the significance of this device in the English writing. The following are the four functions: an effective means of emphasis; making anidea clear and easier; generating emotional force; heightening a certain atmosphere.

  16. Synesthesia in twins: incomplete concordance in monozygotes suggests extragenic factors.

    Science.gov (United States)

    Bosley, Hannah G; Eagleman, David M

    2015-06-01

    Colored-sequence synesthesia (CSS) is a neurological condition in which sequential stimuli such as letters, numbers, or days of the week trigger simultaneous, involuntary color perception. Although the condition appears to run in families and several studies have sought a genetic link, the genetic contribution to synesthesia remains unclear. We conducted the first comparative twin study of CSS and found that CSS has a pairwise concordance of 73.9% in monozygotic twins, and a pairwise concordance of 36.4% in dizygotic twins. In line with previous studies, our results suggest a heritable element of synesthesia. However, consonant with the findings of previous single-pair case studies, our large sample size verifies that synesthesia is not completely conferred by genetics; if it were, monozygotic twins should have 100% concordance. These findings implicate a genetic mechanism of CSS that may work differently than previously thought: collectively, our data suggest that synesthesia is a heritable condition with incomplete penetrance that is substantially influenced by epigenetic and environmental factors. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Variations in Repetition Duration and Repetition Numbers Influence Muscular Activation and Blood Lactate Response in Protocols Equalized by Time Under Tension.

    Science.gov (United States)

    Lacerda, Lucas T; Martins-Costa, Hugo C; Diniz, Rodrigo C R; Lima, Fernando V; Andrade, André G P; Tourino, Frank D; Bemben, Michael G; Chagas, Mauro H

    2016-01-01

    The aim of this study was to investigate the impact of protocols equalized by the time under tension (TUT) but composed of different repetition durations and repetitions numbers on muscle activation and blood lactate concentration. Twenty-two males with previous experience in resistance training performed 2 training protocols (A and B) with the Smith machine bench press exercise, both with 3 sets, 3 minutes' rest, and 60% of 1 repetition maximum (1RM). Protocol A consisted of 6 repetitions with a 6-second repetition duration for each repetition, whereas in Protocol B the subjects performed 12 repetitions with a 3-second repetition duration for each repetition. Muscular activation was measured in the anterior deltoid, pectoralis major, and triceps brachii muscles while performing the 2 protocols, and the normalized root mean square of the electromyographic signal (EMGRMS) was calculated for each set. Blood lactate concentrations were measured during and until 12 minutes after the completion of each protocol. The results showed that the EMGRMS of all muscles increased during the sets and was higher in Protocol B when compared with Protocol A. Likewise, blood lactate concentrations also increased throughout the sets and were higher in Protocol B both during and after the completion of each training session. The data obtained in this study show that training protocols conducted with the same TUT, but with different configurations, produce distinct neuromuscular and metabolic responses so that performing higher repetition numbers with shorter repetition durations might be a more appropriate strategy to increase muscle activation and blood lactate concentration.

  18. Handedness, repetitive transcranial magnetic stimulation and bulimic disorders.

    Science.gov (United States)

    Van den Eynde, F; Broadbent, H; Guillaume, S; Claudino, A; Campbell, I C; Schmidt, U

    2012-05-01

    Repetitive Transcranial Magnetic Stimulation (rTMS) research in psychiatry mostly excludes left-handed participants. We recruited left-handed people with a bulimic disorder and found that stimulation of the left prefrontal cortex may result in different effects in left- and right-handed people. This highlights the importance of handedness and cortex lateralisation for rTMS.

  19. Intrinsic and Extrinsic Motivation for Stereotypic and Repetitive Behavior

    Science.gov (United States)

    Joosten, Annette V.; Bundy, Anita C.; Einfeld, Stewart L.

    2009-01-01

    This study provides evidence for intrinsic and extrinsic motivators for stereotypical and repetitive behavior in children with autism and intellectual disability and children with intellectual disability alone. We modified the Motivation Assessment Scale (MAS) (1988b); dividing it into intrinsic and extrinsic measures and adding items to assess…

  20. Decomposition of Repetition Priming Processes in Word Translation

    Science.gov (United States)

    Francis, Wendy S.; Duran, Gabriela; Augustini, Beatriz K.; Luevano, Genoveva; Arzate, Jose C.; Saenz, Silvia P.

    2011-01-01

    Translation in fluent bilinguals requires comprehension of a stimulus word and subsequent production, or retrieval and articulation, of the response word. Four repetition-priming experiments with Spanish-English bilinguals (N = 274) decomposed these processes using selective facilitation to evaluate their unique priming contributions and factorial…

  1. Auditory Repetition Priming Is Impaired in Pure Alexic Patients

    Science.gov (United States)

    Swick, Diane; Miller, Kimberly M.; Larsen, Jary

    2004-01-01

    Alexia without agraphia, or ''pure'' alexia, is an acquired impairment in reading that leaves writing skills intact. Repetition priming for visually presented words is diminished in pure alexia. However, it is not possible to verify whether this priming deficit is modality-specific or modality independent because reading abilities are compromised.…

  2. Repetition priming-induced changes in sensorimotor transmission.

    Science.gov (United States)

    Svensson, Erik; Evans, Colin G; Cropper, Elizabeth C

    2016-03-01

    When a behavior is repeated performance often improves, i.e., repetition priming occurs. Although repetition priming is ubiquitous, mediating mechanisms are poorly understood. We address this issue in the feeding network ofAplysia Similar to the priming observed elsewhere, priming inAplysiais stimulus specific, i.e., it can be either "ingestive" or "egestive." Previous studies demonstrated that priming alters motor and premotor activity. Here we sought to determine whether sensorimotor transmission is also modified. We report that changes in sensorimotor transmission do occur. We ask how they are mediated and obtain data that strongly suggest a presynaptic mechanism that involves changes in the "background" intracellular Ca(2+)concentration ([Ca(2+)]i) in primary afferents themselves. This form of plasticity has previously been described and generated interest due to its potentially graded nature. Manipulations that alter the magnitude of the [Ca(2+)]iimpact the efficacy of synaptic transmission. It is, however, unclear how graded control is exerted under physiologically relevant conditions. In the feeding system changes in the background [Ca(2+)]iare mediated by the induction of a nifedipine-sensitive current. We demonstrate that the extent to which this current is induced is altered by peptides (i.e., increased by a peptide released during the repetition priming of ingestive activity and decreased by a peptide released during the repetition priming of egestive activity). We suggest that this constitutes a behaviorally relevant mechanism for the graded control of synaptic transmission via the regulation of the [Ca(2+)]iin a neuron.

  3. A Study on Repetition Techniques in Persian Morphology

    Directory of Open Access Journals (Sweden)

    a Vafaie

    2011-06-01

    Full Text Available The speakers of any language, according to their constant need, coin some novel words in order to convey meaning, express ideas, thoughts, and their desires. In this process, they take advantage of their overt or covert linguistic competence. For instance, the derivative feature of Arabic language has contributed a lot to speakers of that language to create so many words with multiple meanings, all formed on the same stem. Likewise, English speakers make use of the derivative features, compounding, blending, and multiple processes of their language to create words. Similarly, in Persian language, the speakers make new words based on specific features of that language. There are five common processes applied in Persian language to form new words, among which blending, compounding, derivation, repetition or reduplication, clipping and acronyms are frequently used and the other techniques or processes have been neglected. Word repetition is one of the word formation processes and many words are made through this process. This study is an attempt to delve into the morphological processes of word repetition in Persian contemporary language according to the texts of three books, “Imaginary Perspectives in Persian Poetry”, “Let’s Listen to the Speech” and “with Holleh Convoy”. In addition, it strives to find a proper solution to the question of the Persian word formation processes in creating new words through repetition.

  4. Do Stimulus-Action Associations Contribute to Repetition Priming?

    Science.gov (United States)

    Dennis, Ian; Perfect, Timothy J.

    2013-01-01

    Despite evidence that response learning makes a major contribution to repetition priming, the involvement of response representations at the level of motor actions remains uncertain. Levels of response representation were investigated in 4 experiments that used different tasks at priming and test. Priming for stimuli that required congruent…

  5. Processing Speaker Variability in Repetition and Semantic/Associative Priming

    Science.gov (United States)

    Lee, Chao-Yang; Zhang, Yu

    2015-01-01

    The effect of speaker variability on accessing the form and meaning of spoken words was evaluated in two short-term priming experiments. In the repetition priming experiment, participants listened to repeated or unrelated prime-target pairs, in which the prime and target were produced by the same speaker or different speakers. The results showed…

  6. Autism and exergaming: effects on repetitive behaviors and cognition.

    Science.gov (United States)

    Anderson-Hanley, Cay; Tureck, Kimberly; Schneiderman, Robyn L

    2011-01-01

    Autism is a neurodevelopmental disorder that leads to impairment in social skills and delay in language development, and results in repetitive behaviors and restricted interests that impede academic and social involvement. Physical exercise has been shown to decrease repetitive behaviors in autistic children and improve cognitive function across the life-span. Exergaming combines physical and mental exercise simultaneously by linking physical activity movements to video game control and may yield better compliance with exercise. In this investigation, two pilot studies explored the potential behavioral and cognitive benefits of exergaming. In Pilot I, twelve children with autism spectrum disorders completed a control task and an acute bout of Dance Dance Revolution (DDR); in Pilot II, ten additional youths completed an acute bout of cyber cycling. Repetitive behaviors and executive function were measured before and after each activity. Repetitive behaviors significantly decreased, while performance on Digits Backwards improved following the exergaming conditions compared with the control condition. Additional research is needed to replicate these findings, and to explore the application of exergaming for the management of behavioral disturbance and to increase cognitive control in children on the autism spectrum.

  7. Orientation-Invariant Object Recognition: Evidence from Repetition Blindness

    Science.gov (United States)

    Harris, Irina M.; Dux, Paul E.

    2005-01-01

    The question of whether object recognition is orientation-invariant or orientation-dependent was investigated using a repetition blindness (RB) paradigm. In RB, the second occurrence of a repeated stimulus is less likely to be reported, compared to the occurrence of a different stimulus, if it occurs within a short time of the first presentation.…

  8. Piriform spider silk sequences reveal unique repetitive elements.

    Science.gov (United States)

    Perry, David J; Bittencourt, Daniela; Siltberg-Liberles, Jessica; Rech, Elibio L; Lewis, Randolph V

    2010-11-08

    Orb-weaving spider silk fibers are assembled from very large, highly repetitive proteins. The repeated segments contain, in turn, short, simple, and repetitive amino acid motifs that account for the physical and mechanical properties of the assembled fiber. Of the six orb-weaver silk fibroins, the piriform silk that makes the attachment discs, which lashes the joints of the web and attaches dragline silk to surfaces, has not been previously characterized. Piriform silk protein cDNAs were isolated from phage libraries of three species: A. trifasciata , N. clavipes , and N. cruentata . The deduced amino acid sequences from these genes revealed two new repetitive motifs: an alternating proline motif, where every other amino acid is proline, and a glutamine-rich motif of 6-8 amino acids. Similar to other spider silk proteins, the repeated segments are large (>200 amino acids) and highly homogenized within a species. There is also substantial sequence similarity across the genes from the three species, with particular conservation of the repetitive motifs. Northern blot analysis revealed that the mRNA is larger than 11 kb and is expressed exclusively in the piriform glands of the spider. Phylogenetic analysis of the C-terminal regions of the new proteins with published spidroins robustly shows that the piriform sequences form an ortholog group.

  9. Focus on form through task repetition in TBLT

    NARCIS (Netherlands)

    van de Guchte, M.; Braaksma, M.; Rijlaarsdam, G.; Bimmel, P.

    2015-01-01

    Because there has been little research on focus on form during the post-task phase in task-based language teaching, this experimental study investigates the effects of task repetition after having directed learners’ attention to form during the main task. The study comprises two interventions, where

  10. The neurobiology of repetitive behavior: …and men

    NARCIS (Netherlands)

    Langen, Marieke; Durston, Sarah; Kas, Martien J H; van Engeland, Herman; Staal, Wouter G

    2011-01-01

    In young, typically developing children, repetitive behavior similar to that in certain neuropsychiatric syndromes is common. Whereas this behavior is adaptive in typical development, in many disorders it forms a core component of symptoms and causes prominent impairment in the daily life of affecte

  11. Spierbelasting en RSI [Muscle load and repetitive strain injury (RSI)

    NARCIS (Netherlands)

    Hoozemans, M.J.M.; Visser, B.; Huysmans, M.A.; Speklé, E.M.; Dieën, J.H. van

    2005-01-01

    This paper presents an overview of theories concerning the development of RSI (repetitive strain injury), related to muscle disorders. Movement is a noisy process. The level of noise is affected by factors such as fatigue and psychosocial stress. In order for precision movements to be made in such

  12. Use of Repetitive Transcranial Magnetic Stimulation for Treatment in Psychiatry

    NARCIS (Netherlands)

    Aleman, Andre

    The potential of noninvasive neurostimulation by repetitive transcranial magnetic stimulation (rTMS) for improving psychiatric disorders has been studied increasingly over the past two decades. This is especially the case for major depression and for auditory verbal hallucinations in schizophrenia.

  13. Practicing novel, praxis-like movements: physiological effects of repetition

    Directory of Open Access Journals (Sweden)

    Joshua Benjamin Ewen

    2016-02-01

    Full Text Available Our primary goal was to develop and validate a task that could provide evidence about how humans learn praxis gestures, such as those involving the use of tools. To that end, we created a video-based task in which subjects view a model performing novel, meaningless one-handed actions with kinematics similar to praxis gestures. Subjects then imitated the movements with their right hand. Trials were repeated 6 times to examine practice effects. EEG was recorded during the task. As a control, subjects watched videos of a model performing a well-established (over learned tool-use gesture. These gestures were also imitated 6 times. Demonstrating convergent validity, EEG measures of task-related cortical activation were similar in topography and frequency between the novel gesture task and the overlearned, praxis gesture task. As in studies assessing motor skill learning with simpler tasks, cortical activation during novel gesture learning decreased as the same gestures were repeated. In the control condition, repetition of overlearned tool-use gestures were also associated with reductions in activation, though to a lesser degree. Given that even overlearned, praxis gestures show constriction of EEG activity with repetition, it is possible that that attentional effects drive some of the repetition effects seen in EEG measures of activation during novel gesture repetition.

  14. A repetitive 0.14 THz relativistic surface wave oscillator

    Energy Technology Data Exchange (ETDEWEB)

    Wang Guangqiang; Tong Changjiang; Li Xiaoze; Wang Xuefeng; Li Shuang; Lu Xicheng [Northwest Institute of Nuclear Technology, P.O. Box 69-1, Xi' an 710024 (China); Wang Jianguo [Northwest Institute of Nuclear Technology, P.O. Box 69-1, Xi' an 710024 (China); School of Electronic and Information Engineering, Xi' an Jiaotong University, Xi' an 710049 (China)

    2013-04-15

    Preliminary experimental results of a repetitive 0.14 THz overmoded relativistic surface wave oscillator (RSWO) are presented in this paper. The repetitive RSWO is developed by using a rectangularly corrugated slow-wave structure with overmoded ratio of 3 and a foilless diode emitting annular electron beam with thickness of 0.5 mm. The high quality electron beams at the repetition rate of 10 are obtained over a wide range of diode voltage (180 kV < U < 240 kV) and current (700 A < I < 1.2 kA). The generation experiments of RSWO are conducted at an axial pulsed magnetic field whose maximum strength and duration can reach about 2.7 T and 1 s, respectively. The experimental results show that the RSWO successfully produces reasonable uniform terahertz pulses at repetition rate of 10, and the pulse duration, frequency, and power of a single pulse are about 1.5 ns, 0.154 THz, and 2.6 MW, respectively, whereas the dominated radiation mode of the RSWO is TM{sub 02}.

  15. Memory, emotion, and pupil diameter: Repetition of natural scenes.

    Science.gov (United States)

    Bradley, Margaret M; Lang, Peter J

    2015-09-01

    Recent studies have suggested that pupil diameter, like the "old-new" ERP, may be a measure of memory. Because the amplitude of the old-new ERP is enhanced for items encoded in the context of repetitions that are distributed (spaced), compared to massed (contiguous), we investigated whether pupil diameter is similarly sensitive to repetition. Emotional and neutral pictures of natural scenes were viewed once or repeated with massed (contiguous) or distributed (spaced) repetition during incidental free viewing and then tested on an explicit recognition test. Although an old-new difference in pupil diameter was found during successful recognition, pupil diameter was not enhanced for distributed, compared to massed, repetitions during either recognition or initial free viewing. Moreover, whereas a significant old-new difference was found for erotic scenes that had been seen only once during encoding, this difference was absent when erotic scenes were repeated. Taken together, the data suggest that pupil diameter is not a straightforward index of prior occurrence for natural scenes. © 2015 Society for Psychophysiological Research.

  16. Processing Speaker Variability in Repetition and Semantic/Associative Priming

    Science.gov (United States)

    Lee, Chao-Yang; Zhang, Yu

    2015-01-01

    The effect of speaker variability on accessing the form and meaning of spoken words was evaluated in two short-term priming experiments. In the repetition priming experiment, participants listened to repeated or unrelated prime-target pairs, in which the prime and target were produced by the same speaker or different speakers. The results showed…

  17. Do Stimulus-Action Associations Contribute to Repetition Priming?

    Science.gov (United States)

    Dennis, Ian; Perfect, Timothy J.

    2013-01-01

    Despite evidence that response learning makes a major contribution to repetition priming, the involvement of response representations at the level of motor actions remains uncertain. Levels of response representation were investigated in 4 experiments that used different tasks at priming and test. Priming for stimuli that required congruent…

  18. Finite-Repetition threshold for infinite ternary words

    Directory of Open Access Journals (Sweden)

    Golnaz Badkobeh

    2011-08-01

    Full Text Available The exponent of a word is the ratio of its length over its smallest period. The repetitive threshold r(a of an a-letter alphabet is the smallest rational number for which there exists an infinite word whose finite factors have exponent at most r(a. This notion was introduced in 1972 by Dejean who gave the exact values of r(a for every alphabet size a as it has been eventually proved in 2009. The finite-repetition threshold for an a-letter alphabet refines the above notion. It is the smallest rational number FRt(a for which there exists an infinite word whose finite factors have exponent at most FRt(a and that contains a finite number of factors with exponent r(a. It is known from Shallit (2008 that FRt(2=7/3. With each finite-repetition threshold is associated the smallest number of r(a-exponent factors that can be found in the corresponding infinite word. It has been proved by Badkobeh and Crochemore (2010 that this number is 12 for infinite binary words whose maximal exponent is 7/3. We show that FRt(3=r(3=7/4 and that the bound is achieved with an infinite word containing only two 7/4-exponent words, the smallest number. Based on deep experiments we conjecture that FRt(4=r(4=7/5. The question remains open for alphabets with more than four letters. Keywords: combinatorics on words, repetition, repeat, word powers, word exponent, repetition threshold, pattern avoidability, word morphisms.

  19. Investigating repetition and change in musical rhythm by functional MRI.

    Science.gov (United States)

    Danielsen, A; Otnæss, M K; Jensen, J; Williams, S C R; Ostberg, B C

    2014-09-05

    Groove-based rhythm is a basic and much appreciated feature of Western popular music. It is commonly associated with dance, movement and pleasure and is characterized by the repetition of a basic rhythmic pattern. At various points in the musical course, drum breaks occur, representing a change compared to the repeated pattern of the groove. In the present experiment, we investigated the brain response to such drum breaks in a repetitive groove. Participants were scanned with functional magnetic resonance imaging (fMRI) while listening to a previously unheard naturalistic groove with drum breaks at uneven intervals. The rhythmic pattern and the timing of its different parts as performed were the only aspects that changed from the repetitive sections to the breaks. Differences in blood oxygen level-dependent activation were analyzed. In contrast to the repetitive parts, the drum breaks activated the left cerebellum, the right inferior frontal gyrus (RIFG), and the superior temporal gyri (STG) bilaterally. A tapping test using the same stimulus showed an increase in the standard deviation of inter-tap-intervals in the breaks versus the repetitive parts, indicating extra challenges for auditory-motor integration in the drum breaks. Both the RIFG and STG have been associated with structural irregularity and increase in musical-syntactical complexity in several earlier studies, whereas the left cerebellum is known to play a part in timing. Together these areas may be recruited in the breaks due to a prediction error process whereby the internal model is being updated. This concurs with previous research suggesting a network for predictive feed-forward control that comprises the cerebellum and the cortical areas that were activated in the breaks.

  20. Active power filter for harmonic compensation using a digital dual-mode-structure repetitive control approach

    DEFF Research Database (Denmark)

    Zou, Zhixiang; Wang, Zheng; Cheng, Ming;

    2012-01-01

    This paper presents an digital dual-mode-structure repetitive control approach for the single-phase shunt active power filter (APF), which aims to enhance the tracking ability and eliminate arbitrary order harmonic. The proposed repetitive control scheme blends the characteristics of both odd......-harmonic repetitive control and even-harmonic repetitive control. Moreover, the convergence rate is faster than conventional repetitive controller. Additionally, the parameters have been designed and optimized for the dual-mode structure repetitive control to improve the performance of APF system. Experimental...... results on a laboratory setup are given to verify the proposed control scheme....

  1. A New Revised DNA Cramp Tool Based Approach of Chopping DNA Repetitive and Non-Repetitive Genome Sequences

    Directory of Open Access Journals (Sweden)

    V.Hari Prasad

    2012-11-01

    Full Text Available In vogue tremendous amount of data generated day by day by the living organism of genetic sequences and its accumulation in database, their size is growing in an exponential manner. Due to excessive storage of DNA sequences in public databases like NCBI, EMBL and DDBJ archival maintenance is tedious task. Transmission of information from one place to another place in network management systems is also a critical task. So To improve the efficiency and to reduce the overhead of the database need of compression arises in database optimization. In this connection different techniques were bloomed, but achieved results are not bountiful. Many classical algorithms are fails to compress genetic sequences due to the specificity of text encoded in dna and few of the existing techniques achieved positive results. DNA is repetitive and non repetitive in nature. Our proposed technique DNACRAMP is applicable on repetitive and non repetitive sequences of dna and it yields better compression ratio in terms of bits per bases. This is compared with existing techniques and observed that our one is the optimum technique and compression results are on par with existing techniques.

  2. 76 FR 44489 - Medical Devices; Neurological Devices; Classification of Repetitive Transcranial Magnetic...

    Science.gov (United States)

    2011-07-26

    ... transcranial magnetic stimulation (rTMS) system into class II (special controls). The Agency is classifying...; Classification of Repetitive Transcranial Magnetic Stimulation System AGENCY: Food and Drug Administration, HHS... entitled ``Class II Special Controls Guidance Document: Repetitive Transcranial Magnetic......

  3. Repetitive motion planning and control of redundant robot manipulators

    CERN Document Server

    Zhang, Yunong

    2013-01-01

    Repetitive Motion Planning and Control of Redundant Robot Manipulators presents four typical motion planning schemes based on optimization techniques, including the fundamental RMP scheme and its extensions. These schemes are unified as quadratic programs (QPs), which are solved by neural networks or numerical algorithms. The RMP schemes are demonstrated effectively by the simulation results based on various robotic models; the experiments applying the fundamental RMP scheme to a physical robot manipulator are also presented. As the schemes and the corresponding solvers presented in the book have solved the non-repetitive motion problems existing in redundant robot manipulators, it is of particular use in applying theoretical research based on the quadratic program for redundant robot manipulators in industrial situations. This book will be a valuable reference work for engineers, researchers, advanced undergraduate and graduate students in robotics fields. Yunong Zhang is a professor at The School of Informa...

  4. Perseveration and other repetitive verbal behaviors: functional dissociations.

    Science.gov (United States)

    Christman, Sarah S; Boutsen, Frank R; Buckingham, Hugh W

    2004-11-01

    This article will review types of perseveration from a neurolinguistic perspective. During the course of the article, continuous, stuck-in-set, and recurrent perseveration will be placed in contradistinction to several other types of repetitive behaviors commonly associated with neurogenic communication disorders. These include echolalia in mixed transcortical aphasia; conduite d'approche and conduite d'ecart in fluent aphasias; lexical and nonlexical automatisms in nonfluent aphasias; palilalia in neuromotor disorders, such as Parkinson's disease (PD); and sound, syllable, word, and phrase repetitions in neurogenic stuttering. When differentiating these phenomena from perseveration, it is helpful to consider the salient factors that condition observed behaviors in individual patients, such as overall speech fluency, inventory of available utterances, nature of eliciting tasks, and propositionality of responses. Information such as communication disorder diagnosis, underlying etiology, and known sites of lesion from each patient's total clinical profile may also assist with differentiation.

  5. Fine tuning of micropillar cavity modes through repetitive oxidations

    CERN Document Server

    Bakker, Morten P; Snijders, Henk; Truong, Tuan-Ahn; Petroff, Pierre M; Bouwmeester, Dirk; van Exter, Martin P

    2013-01-01

    Repetitive wet thermal oxidations of a tapered oxide aperture in a micropillar structure are demonstrated. After each oxidation step the con?fined optical modes are analyzed at room temperature. Three regimes are identi?fied. First, the optical con?finement increases when the aperture oxidizes towards the center. Then, the cavity modes shift by more than 30 nm, when the taper starts to oxidize through the center, leading to a decrease in the optical path length. Finally, the resonance frequency levels o?f, when the aperture is oxidized all the way through the micropillar, but confi?ned optical modes with a high quality factor remain. This repetitive oxidation technique therefore enables precise control of the optical cavity volume or wavelength.

  6. Interaction of Repetitively Pulsed High Energy Laser Radiation With Matter

    Science.gov (United States)

    Hugenschmidt, Manfred

    1986-10-01

    The paper is concerned with laser target interaction processes involving new methods of improving the overall energy balance. As expected theoretically, this can be achieved with high repetition rate pulsed lasers even for initially highly reflecting materials, such as metals. Experiments were performed by using a pulsed CO2 laser at mean powers up to 2 kW and repetition rates up to 100 Hz. The rates of temperature rise of aluminium for example were thereby increased by lore than a factor of 3 as compared to cw-radiation of comparable power density. Similar improvements were found for the overall absorptivities that were increased by this method by more than an order of magnitude.

  7. Skill learning and repetition priming in Alzheimer's disease.

    Science.gov (United States)

    Grober, E; Ausubel, R; Sliwinski, M; Gordon, B

    1992-10-01

    While perceptual-motor learning occurs normally in Alzheimer's disease (AD) patients, their ability to acquire the skill of reading transformed text has not been well delineated. AD patients and matched controls were timed as they read two blocks of words presented in mirror image. Control subjects displayed both skill learning and repetition priming, whereas AD patients displayed only repetition priming. Skill learning in AD patients was associated with their ability to complete verbal analogies. They displayed the expected impairment in recognition for the words from the mirror reading task. The failure of AD patients to acquire the mirror reading skill can be understood through a task analysis and may reflect an underlying deficit in abstract reasoning that precludes the development of appropriate pattern analyzing strategies needed to transform rotated text.

  8. Scan patterns when viewing natural scenes: emotion, complexity, and repetition.

    Science.gov (United States)

    Bradley, Margaret M; Houbova, Petra; Miccoli, Laura; Costa, Vincent D; Lang, Peter J

    2011-11-01

    Eye movements were monitored during picture viewing, and effects of hedonic content, perceptual composition, and repetition on scanning assessed. In Experiment 1, emotional and neutral pictures that were figure-ground compositions or more complex scenes were presented for a 6-s free viewing period. Viewing emotional pictures or complex scenes prompted more fixations and broader scanning of the visual array, compared to neutral pictures or simple figure-ground compositions. Effects of emotion and composition were independent, supporting the hypothesis that these oculomotor indices reflect enhanced information seeking. Experiment 2 tested an orienting hypothesis by repeatedly presenting the same pictures. Although repetition altered specific scan patterns, emotional, compared to neutral, picture viewing continued to prompt oculomotor differences, suggesting that motivationally relevant cues enhance information seeking in appetitive and defensive contexts. Copyright © 2011 Society for Psychophysiological Research.

  9. Repetitive transients extraction algorithm for detecting bearing faults

    Science.gov (United States)

    He, Wangpeng; Ding, Yin; Zi, Yanyang; Selesnick, Ivan W.

    2017-02-01

    Rolling-element bearing vibrations are random cyclostationary. This paper addresses the problem of noise reduction with simultaneous components extraction in vibration signals for faults diagnosis of bearing. The observed vibration signal is modeled as a summation of two components contaminated by noise, and each component composes of repetitive transients. To extract the two components simultaneously, an approach by solving an optimization problem is proposed in this paper. The problem adopts convex sparsity-based regularization scheme for decomposition, and non-convex regularization is used to further promote the sparsity but preserving the global convexity. A synthetic example is presented to illustrate the performance of the proposed approach for repetitive feature extraction. The performance and effectiveness of the proposed method are further demonstrated by applying to compound faults and single fault diagnosis of a locomotive bearing. The results show the proposed approach can effectively extract the features of outer and inner race defects.

  10. Improved Discrimination of Visual Stimuli Following Repetitive Transcranial Magnetic Stimulation

    OpenAIRE

    Waterston, Michael L.; Pack, Christopher C.

    2010-01-01

    BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) at certain frequencies increases thresholds for motor-evoked potentials and phosphenes following stimulation of cortex. Consequently rTMS is often assumed to introduce a "virtual lesion" in stimulated brain regions, with correspondingly diminished behavioral performance. METHODOLOGY/PRINCIPAL FINDINGS: Here we investigated the effects of rTMS to visual cortex on subjects' ability to perform visual psychophysical tasks. Contrary t...

  11. Striatal development in autism: repetitive behaviors and the reward circuitry

    OpenAIRE

    Kohls, Gregor; Yerys, Benjamin; Schultz, Robert T

    2014-01-01

    Autism spectrum disorder (ASD) is defined by two essential features – impaired social communication abilities, including deficits with social reciprocity, nonverbal communication and establishing relationships, and by the presence of restricted and repetitive behaviors and interests (RRBIs). Social deficits get the majority of attention both in science and in the popular media, but RRBIs are equally important in understanding autism. Although RRBIs are also seen in typically...

  12. Illusory sensation of movement induced by repetitive transcranial magnetic stimulation

    OpenAIRE

    Mark Schram Christensen; Jesper Lundbye-Jensen; Michael James Grey; Alexandra Damgaard Vejlby; Bo Belhage; Jens Bo Nielsen

    2010-01-01

    Human movement sense relies on both somatosensory feedback and on knowledge of the motor commands used to produce the movement. We have induced a movement illusion using repetitive transcranial magnetic stimulation over primary motor cortex and dorsal premotor cortex in the absence of limb movement and its associated somatosensory feedback. Afferent and efferent neural signalling was abolished in the arm with ischemic nerve block, and in the leg with spinal nerve block. Movement sensation was...

  13. Scan patterns when viewing natural scenes: Emotion, complexity, and repetition

    OpenAIRE

    Bradley, Margaret M.; Houbova, Petra; Miccoli,Laura; Costa, Vincent D.; Lang, Peter J.

    2011-01-01

    Eye movements were monitored during picture viewing and effects of hedonic content, perceptual composition, and repetition on scanning assessed. In Experiment 1, emotional and neutral pictures that were figure-ground compositions or more complex scenes were presented for a 6 s free viewing period. Viewing emotional pictures or complex scenes prompted more fixations and broader scanning of the visual array, compared to neutral pictures or simple figure-ground compositions. Effects of emotion a...

  14. Route to 100 TW Ti: Sapphire laser at repetitive mode

    Directory of Open Access Journals (Sweden)

    Teng Hao

    2013-11-01

    Full Text Available We demonstrated a 100 TW-class femtosecond Ti: sapphire laser running at repetition rate of 0.1 Hz by adding a stage amplifier in the 20 TW/10 Hz laser facility (XL-II. Pumping the new stage amplifier with the 25 J green Nd:glass laser, we successfully upgraded the laser energy to 3.4 J with duration of 29 fs, corresponding to a peak power of 117 TW.

  15. Don't Throw out the Baby with the Bathwater: Verbal Repetition, Mnemonics, and Active Learning

    Science.gov (United States)

    Saber, Jane Lee; Johnson, Richard D.

    2008-01-01

    The effectiveness of using verbal repetition and first-letter acronyms to teach a common marketing framework was examined in two experiments. In Experiment 1, 345 undergraduate students were exposed to the framework using one of four conditions: control, verbal repetition, acronym, and verbal repetition plus acronym in a traditional learning…

  16. Examining Restricted and Repetitive Behaviors in Young Children with Autism Spectrum Disorder during Two Observational Contexts

    Science.gov (United States)

    Stronach, Sheri; Wetherby, Amy M.

    2014-01-01

    This prospective study of the FIRST WORDS® Project examined restricted and repetitive behaviors in a sample of 55 toddlers at a mean age of 20 months who were later diagnosed with autism spectrum disorder. Restricted and repetitive behaviors were coded using the Repetitive Movement and Restricted Interest Scales in two video-recorded observation…

  17. Characterizing Caregiver Responses to Restricted and Repetitive Behaviors in Toddlers with Autism Spectrum Disorder

    Science.gov (United States)

    Harrop, Clare; Gulsrud, Amanda; Shih, Wendy; Hovsepyan, Lilit; Kasari, Connie

    2016-01-01

    Restricted and repetitive behaviors are a core feature of autism spectrum disorder. This descriptive study documented the presence of restricted and repetitive behaviors in 85 toddlers with autism spectrum disorder as they interacted with their caregiver in a play interaction. For each child restricted and repetitive behavior, a caregiver…

  18. On the repetitive operation of a self-switched transversely excited atmosphere CO2 laser

    Indian Academy of Sciences (India)

    Pallavi Raote; Gautam Patil; J Padma Nilaya; D J Biswas

    2010-11-01

    The repetition rate capability of self-switched transversely excited atmosphere (TEA) CO2 laser was studied for different gas flow configurations. For an optimized gas flow configuration, repetitive operation was achieved at a much smaller gas replenishment factor between two successive pulses when compared with repetitive systems energized by conventional pulsers.

  19. Effects of Material Emotional Valence on the Time Course of Massive Repetition Priming

    Science.gov (United States)

    Hu, Zhiguo; Liu, Hongyan; Zhang, John X.

    2010-01-01

    Learning through repetition is a fundamental form and also an effective method of language learning critical for achieving proficient and automatic language use. Massive repetition priming as a common research paradigm taps into the dynamic processes involved in repetition learning. Research with this paradigm has so far used only emotionally…

  20. FBFN-based adaptive repetitive control of nonlinearly parameterized systems

    Institute of Scientific and Technical Information of China (English)

    Wenli Sun; Hong Cai; Fu Zhao

    2013-01-01

    An adaptive repetitive control scheme is presented for a class of nonlinearly parameterized systems based on the fuzzy ba-sis function network (FBFN). The parameters of the fuzzy rules are tuned with adaptive schemes. To attenuate chattering effectively, the discontinuous control term is approximated by an adaptive PI control structure. The bound of the discontinuous control term is assumed to be unknown and estimated by an adaptive mecha-nism. Based on the Lyapunov stability theory, an adaptive repeti-tive control law is proposed to guarantee the closed-loop stability and the tracking performance. By means of FBFNs, which avoid the nonlinear parameterization from entering into the adaptive repetitive control, the control er singularity problem is solved. The proposed approach does not require an exact structure of the sys-tem dynamics, and the proposed control er is utilized to control a model of permanent-magnet linear synchronous motor subject to significant disturbances and parameter uncertainties. The simula-tion results demonstrate the effectiveness of the proposed method.

  1. A referential theory of the repetition-induced truth effect.

    Science.gov (United States)

    Unkelbach, Christian; Rom, Sarah C

    2017-03-01

    People are more likely to judge repeated statements as true compared to new statements, a phenomenon known as the illusory truth effect. The currently dominant explanation is an increase in processing fluency caused by prior presentation. We present a new theory to explain this effect. We assume that people judge truth based on coherent references for statements in memory. Due to prior presentation, repeated statements have more coherently linked references; thus, a repetition-induced truth effect follows. Five experiments test this theory. Experiment 1-3 show that both the amount and the coherence of references for a repeated statement influence judged truth. Experiment 4 shows that people also judge new statements more likely "true" when they share references with previously presented statements. Experiment 5 realizes theoretically predicted conditions under which repetition should not influence judged truth. Based on these data, we discuss how the theory relates to other explanations of repetition-induced truth and how it may integrate other truth-related phenomena and belief biases. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Illusory sensation of movement induced by repetitive transcranial magnetic stimulation.

    Directory of Open Access Journals (Sweden)

    Mark Schram Christensen

    Full Text Available Human movement sense relies on both somatosensory feedback and on knowledge of the motor commands used to produce the movement. We have induced a movement illusion using repetitive transcranial magnetic stimulation over primary motor cortex and dorsal premotor cortex in the absence of limb movement and its associated somatosensory feedback. Afferent and efferent neural signalling was abolished in the arm with ischemic nerve block, and in the leg with spinal nerve block. Movement sensation was assessed following trains of high-frequency repetitive transcranial magnetic stimulation applied over primary motor cortex, dorsal premotor cortex, and a control area (posterior parietal cortex. Magnetic stimulation over primary motor cortex and dorsal premotor cortex produced a movement sensation that was significantly greater than stimulation over the control region. Movement sensation after dorsal premotor cortex stimulation was less affected by sensory and motor deprivation than was primary motor cortex stimulation. We propose that repetitive transcranial magnetic stimulation over dorsal premotor cortex produces a corollary discharge that is perceived as movement.

  3. Route Repetition and Route Retracing: Effects of Cognitive Aging

    Directory of Open Access Journals (Sweden)

    Jan Malte Wiener

    2012-05-01

    Full Text Available Retracing a recently traveled route is a frequent navigation task when learning novel routes or exploring unfamiliar environments. In the present study we utilized virtual environments technology to investigate age-related differences in repeating and retracing a learned route. In the training phase of the experiment participants were guided along a route consisting of multiple intersections each featuring one unique landmark. In the subsequent test phase, they were guided along short sections of the route and asked to indicate overall travel direction (repetition or retracing, the direction required to continue along the route, and the next landmark they would encounter. Results demonstrate age-related deficits in all three tasks. More specifically, in contrast to younger participants, the older participants had greater problems during route retracing than during route repetition. While route repetition can be solved with egocentric response or route strategies, successfully retracing a route requires allocentric processing. The age-related deficits in route retracing are discussed in the context of impaired allocentric processing and shifts from allocentric to egocentric navigation strategies as a consequence of age-related hippocampal degeneration.

  4. Repetitive motor behavior: further characterization of development and temporal dynamics.

    Science.gov (United States)

    Muehlmann, Amber M; Bliznyuk, Nikolay; Duerr, Isaac; Lewis, Mark H

    2015-03-01

    Repetitive behaviors are diagnostic for autism spectrum disorders, common in related neurodevelopmental disorders, and normative in typical development. In order to identify factors that mediate repetitive behavior development, it is necessary to characterize the expression of these behaviors from an early age. Extending previous findings, we characterized further the ontogeny of stereotyped motor behavior both in terms of frequency and temporal organization in deer mice. A three group trajectory model provided a good fit to the frequencies of stereotyped behavior across eight developmental time points. Group based trajectory analysis using a measure of temporal organization of stereotyped behavior also resulted in a three group solution. Additionally, as the frequency of stereotyped behavior increased with age, the temporal distribution of stereotyped responses became increasingly regular or organized indicating a strong association between these measures. Classification tree and principal components analysis showed that accurate classification of trajectory group could be done with fewer observations. This ability to identify trajectory group membership earlier in development allows for examination of a wide range of variables, both experiential and biological, to determine their impact on altering the expected trajectory of repetitive behavior across development. Such studies would have important implications for treatment efforts in neurodevelopmental disorders such as autism.

  5. Repetition suppression: a means to index neural representations using BOLD?

    Science.gov (United States)

    Behrens, Timothy E. J.

    2016-01-01

    Understanding how the human brain gives rise to complex cognitive processes remains one of the biggest challenges of contemporary neuroscience. While invasive recording in animal models can provide insight into neural processes that are conserved across species, our understanding of cognition more broadly relies upon investigation of the human brain itself. There is therefore an imperative to establish non-invasive tools that allow human brain activity to be measured at high spatial and temporal resolution. In recent years, various attempts have been made to refine the coarse signal available in functional magnetic resonance imaging (fMRI), providing a means to investigate neural activity at the meso-scale, i.e. at the level of neural populations. The most widely used techniques include repetition suppression and multivariate pattern analysis. Human neuroscience can now use these techniques to investigate how representations are encoded across neural populations and transformed by relevant computations. Here, we review the physiological basis, applications and limitations of fMRI repetition suppression with a brief comparison to multivariate techniques. By doing so, we show how fMRI repetition suppression holds promise as a tool to reveal complex neural mechanisms that underlie human cognitive function. This article is part of the themed issue ‘Interpreting BOLD: a dialogue between cognitive and cellular neuroscience’. PMID:27574308

  6. Assessing maladaptive repetitive thought in clinical disorders: A critical review of existing measures.

    Science.gov (United States)

    Samtani, Suraj; Moulds, Michelle L

    2017-04-01

    Rumination and worry have recently been grouped under the broader transdiagnostic construct of repetitive thought (Watkins, 2008). The purpose of this review is to provide an overview of scales used to assess repetitive thinking across a broad range of contexts: depression, anxiety, trauma, stress, illness, interpersonal difficulties, positive affect, and so forth. We also include scales developed or adapted for children and adolescents. In the extant literature, measures of repetitive thinking generally show small-to-moderate correlations with measures of psychopathology. This review highlights problems with the content validity of existing instruments; for example, confounds between repetitive thought and symptomatology, metacognitive beliefs, and affect. This review also builds on previous reviews by including newer transdiagnostic measures of repetitive thinking. We hope that this review will help to expand our understanding of repetitive thinking beyond the mood and anxiety disorders, and suggest ways forward in the measurement of repetitive thinking in individuals with comorbid conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Spectroscopic Investigation of a Repetitively-Pulsed Nanosecond Discharge

    Science.gov (United States)

    Yee, Benjamin T.

    This work reports on an investigation of a repetitively-pulsed nanosecond discharge (RPND) in helium over a range of 0.3-16.0 Torr. The discharge was studied experimentally via laser-absorption spectroscopy and opticals emission spectroscopy measurements. In concert with the experimental campaign, a global model of a helium plasma was developed with the aid of particle-in-cell simulations. The global model was then used to predict the population kinetics and emissions of the RPND. Synthesis of the results provided new data and insights on the development of the RPND. Among the results were direct measurements of the triplet metastable states during the excitation period. This period was found to be unexpectedly long at low pressures (less than or equal to 1.0 Torr), suggesting an excess in high-energy electrons as compared to an equilibrium distribution. Other phenomena such as a prominent return stroke and additional energy deposition by reflections in the transmission line were also identified. Estimates of the electric field and electron temperatures were obtained for several conditions. Furthermore, several optical methods for electron temperature measurement were evaluated for application to the discharge. Based on the global model simulations, the coronal model was found to apply to the line ratio of the 33S-23Po and 31S-2 1Po transitions, however further work is needed to ascertain its applicability to experimental discharges. These results provide new insight on the development of the repetitively-pulsed nanosecond discharge. Specifically, they reveal new information about the excited state dynamics within the discharge, the non-equilibrium nature of its electrons, and several avenues for future studies. This study extends the present understanding of repetitively-pulsed discharges, and advances the knowledge of energy coupling between electric fields and plasmas.

  8. Refining borders of genome-rearrangements including repetitions

    Directory of Open Access Journals (Sweden)

    JA Arjona-Medina

    2016-10-01

    Full Text Available Abstract Background DNA rearrangement events have been widely studied in comparative genomic for many years. The importance of these events resides not only in the study about relatedness among different species, but also to determine the mechanisms behind evolution. Although there are many methods to identify genome-rearrangements (GR, the refinement of their borders has become a huge challenge. Until now no accepted method exists to achieve accurate fine-tuning: i.e. the notion of breakpoint (BP is still an open issue, and despite repeated regions are vital to understand evolution they are not taken into account in most of the GR detection and refinement methods. Methods and results We propose a method to refine the borders of GR including repeated regions. Instead of removing these repetitions to facilitate computation, we take advantage of them using a consensus alignment sequence of the repeated region in between two blocks. Using the concept of identity vectors for Synteny Blocks (SB and repetitions, a Finite State Machine is designed to detect transition points in the difference between such vectors. The method does not force the BP to be a region or a point but depends on the alignment transitions within the SBs and repetitions. Conclusion The accurate definition of the borders of SB and repeated genomic regions and consequently the detection of BP might help to understand the evolutionary model of species. In this manuscript we present a new proposal for such a refinement. Features of the SBs borders and BPs are different and fit with what is expected. SBs with more diversity in annotations and BPs short and richer in DNA replication and stress response, which are strongly linked with rearrangements.

  9. Effective constitutive relations for large repetitive frame-like structures

    Science.gov (United States)

    Nayfeh, A. H.; Hefzy, M. S.

    1981-01-01

    Effective mechanical properties for large repetitive framelike structures are derived using combinations of strength of material and orthogonal transformation techniques. Symmetry considerations are used in order to identify independent property constants. The actual values of these constants are constructed according to a building block format which is carried out in the three consecutive steps: (1) all basic planar lattices are identified; (2) effective continuum properties are derived for each of these planar basic grids using matrix structural analysis methods; and (3) orthogonal transformations are used to determine the contribution of each basic set to the overall effective continuum properties of the structure.

  10. Phylogenetic analysis of the genus Hordeum using repetitive DNA sequences

    DEFF Research Database (Denmark)

    Svitashev, S.; Bryngelsson, T.; Vershinin, A.

    1994-01-01

    A set of six cloned barley (Hordeum vulgare) repetitive DNA sequences was used for the analysis of phylogenetic relationships among 31 species (46 taxa) of the genus Hordeum, using molecular hybridization techniques. In situ hybridization experiments showed dispersed organization of the sequences...... over all chromosomes of H. vulgare and the wild barley species H. bulbosum, H. marinum and H. murinum. Southern blot hybridization revealed different levels of polymorphism among barley species and the RFLP data were used to generate a phylogenetic tree for the genus Hordeum. Our data are in a good...

  11. REDUCTION APPROACHES FOR VIBRATION CONTROL OF REPETITIVE STRUCTURES

    Institute of Scientific and Technical Information of China (English)

    CHEN Wei-min; SUN Dong-chang; WANG Da-jun; WEI Jian-ping; TONG Li-yong; WANG Quan

    2006-01-01

    The reduction approaches are presented for vibration control of symmetric,cyclic periodic and linking structures. The condensation of generalized coordinates, the locations of sensors and actuators, and the relation between system inputs and control forces are assumed to be set in a symmetric way so that the control system posses the same repetition as the structure considered. By employing proper transformations of condensed generalized coordinates and the system inputs, the vibration control of an entire system can be implemented by carrying out the control of a number of sub-structures, and thus the dimension of the control problem can be significantly reduced.

  12. A Linguistic Analysis of a Textual Repetition in Homer's Iliad

    Directory of Open Access Journals (Sweden)

    Alberto MANCO

    2011-01-01

    Full Text Available In Homer's Iliad can be detected some contiguous repetitions in the text (in the same verse or away from each other in an irrelevant way. They appear different from one another but they are related from semantic and morphological issues. An example is provided by the use of the form Hectōr in conjunction with schesō, the alternative form of ecsō. We argue that this cohesion is not a coincidence and we try to suggest an explanation.

  13. Atypical presentation of NREM arousal parasomnia with repetitive episodes.

    Science.gov (United States)

    Trajanovic, N N; Shapiro, C M; Ong, A

    2007-08-01

    The case report describes a distinct variant of non-REM (Rapid Eye Movement) arousal parasomnia, sleepwalking type, featuring repetitive abrupt arousals, mostly from slow-wave sleep, and various automatisms and semi-purposeful behaviours. The frequency of events and distribution throughout the night presented as a continuous status of parasomnia ('status parasomnicus'). The patient responded well to treatment typically administered for adult NREM parasomnias, and after careful review of the clinical presentation, objective findings and treatment outcome, sleep-related epilepsy was ruled out in favour of parasomnia.

  14. Background music for repetitive task performance of severely retarded individuals.

    Science.gov (United States)

    Richman, J S

    1976-11-01

    Environmental manipulation in the form of specific tempo background music was used to assist in the habilitation of severely retarded persons. Thirty institutionalized retarded males were tested on a repetitive manual performance task judged to be similar to the type of tasks found in sheltered workshops. Each subject received each of the background treatments noncontingently: no music, slow tempo music, regular tempo music, fast tempo music. The results indicated that the regular tempo of background music facilitated the greatest improvement in performance, suggesting that the effect of music on performance is more complex than the issue of contingent presentation.

  15. Repetitively Pulsed Electric Laser Acoustic Studies. Volume 1.

    Science.gov (United States)

    1983-09-01

    INGARD ET AL. SEP 83 UNCLASSIFIED APHAL-IR-83-2858-VOL-1 F336i5 86-C 2848 F/ 0/ 8, EEEmohEEEomhiE EohEEmhohEEEEE mhhhmmomhhlm...TR-83-2058, Vol 9, 0 REPETITIVELY PULSED ELECTRIC LASER ACOUSTIC STUDIES Volume I K. U. INGARD , CHARLES F. MCMILLAN uDEPARTMENT OF AERONAUTICS AND...CONTRACT OR GRANT NUMBER(s) K.U. Ingard and Charles F. McMillan F33615.80-C-2040 9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMENT. PROJECT

  16. High voltage high repetition rate pulse using Marx topology

    Science.gov (United States)

    Hakki, A.; Kashapov, N.

    2015-06-01

    The paper describes Marx topology using MOSFET transistors. Marx circuit with 10 stages has been done, to obtain pulses about 5.5KV amplitude, and the width of the pulses was about 30μsec with a high repetition rate (PPS > 100), Vdc = 535VDC is the input voltage for supplying the Marx circuit. Two Ferrite ring core transformers were used to control the MOSFET transistors of the Marx circuit (the first transformer to control the charging MOSFET transistors, the second transformer to control the discharging MOSFET transistors).

  17. About the Infinite Repetition of Histories in Space

    Directory of Open Access Journals (Sweden)

    Manuel Alfonseca

    2014-08-01

    Full Text Available This paper analyzes two different proposals, one by Ellis and Brundrit, based on classical relativistic cosmology, the other by Garriga and Vilenkin, based on the DH interpretation of quantum mechanics, both concluding that, in an infinite universe, planets and beings must be repeated an infinite number of times. We point to possible shortcomings in these arguments. We conclude that the idea of an infinite repetition of histories in space cannot be considered strictly speaking a consequence of current physics and cosmology. Such ideas should be seen rather as examples of «ironic science» in the terminology of John Horgan.

  18. Development of species-specific DNA probes for Campylobacter jejuni, Campylobacter coli, and Campylobacter lari by polymerase chain reaction fingerprinting

    NARCIS (Netherlands)

    Giesendorf, B A; van Belkum, A; Koeken, A; Stegeman, H; Henkens, M H; van der Plas, J; Goossens, H; Niesters, H G; Quint, W G

    1993-01-01

    The application of polymerase chain reaction (PCR) fingerprinting assays enables discrimination between species and strains of microorganisms. PCR primers aiming at arbitrary sequences in combination with primers directed against the repetitive extragenic palindrome (REP) or enterobacterial repetiti

  19. Development of species-specific DNA probes for Campylobacter jejuni, Campylobacter coli, and Campylobacter lari by polymerase chain reaction fingerprinting

    NARCIS (Netherlands)

    Giesendorf, B A; van Belkum, A; Koeken, A; Stegeman, H; Henkens, M H; van der Plas, J; Goossens, H; Niesters, H G; Quint, W G

    The application of polymerase chain reaction (PCR) fingerprinting assays enables discrimination between species and strains of microorganisms. PCR primers aiming at arbitrary sequences in combination with primers directed against the repetitive extragenic palindrome (REP) or enterobacterial

  20. Genetic diversity and antibiotic resistance profiles of Campylobacter jejuni isolates from poultry and humans in Turkey.

    Science.gov (United States)

    Abay, Secil; Kayman, Tuba; Otlu, Baris; Hizlisoy, Harun; Aydin, Fuat; Ertas, Nurhan

    2014-05-16

    In this study, the investigation of clonal relations between human and poultry Campylobacter jejuni isolates and the determination of susceptibilities of isolates to various antibiotics were aimed. A total of 200 C. jejuni isolates concurrently obtained from 100 chicken carcasses and 100 humans were genotyped by the Pulsed-Field Gel Electrophoresis (PFGE) and automated Repetitive Extragenic Palindromic PCR (Rep-PCR, DiversiLab system) methods and were tested for their susceptibility to six antibiotics with disk diffusion method. The minimum inhibitory concentration (MIC) values of ciprofloxacin (CI), enrofloxacin (EF) and erythromycin (EM) were evaluated by E-test. By using PFGE 174 of (87.0%) the isolates were able to be typed. The clonally related strains were placed in 35 different clusters and 115 different genotypes were obtained. All of the two hundred isolates could be typed by using Rep-PCR and were divided into 133 different genotypes. One hundred and fourteen clonally related isolates (57.0%) were included in 47 clusters. In disk diffusion test, while the susceptibility rates of AMC and S to human and chicken derived C. jejuni isolates were 84.0%-96.0% and 96.0%-98.0%, respectively, all isolates were susceptible to gentamicin. The resistance rates of human isolates to AMP, NA and TE were detected as 44.0%, 84.0% and 38.0% of the resistances of chicken isolates to these antibiotics were 34.0%, 95.0% and 56.0%, respectively. The MIC values of human and chicken isolates to CI, EF and EM were detected as 81.0-93.0%, 85.0-88.0% and 6.0-7.0%, respectively. The clonal proximity rates were detected between human and poultry origin C. jejuni isolates. The discriminatory power of PFGE and Rep-PCR was similar, with Simpson's diversity indexes of 0.993 and 0.995, respectively. Concordance of the two methods as determined by Adjusted Rand coefficient was 0.198 which showed the low congruence between Rep-PCR and PFGE. High rates of quinolone resistance were detected in

  1. Bottle microresonator broadband and low repetition rate frequency comb generator

    CERN Document Server

    Dvoyrin, V

    2016-01-01

    We propose a new type of broadband and low repetition rate frequency comb generator which has the shape of an elongated and nanoscale-shallow optical bottle microresonator created at the surface of an optical fiber. The free spectral range (FSR) of the broadband azimuthal eigenfrequency series of this resonator is the exact multiple of the FSR of the dense and narrowband axial series. The effective radius variation of the microresonator is close to a parabola with a nanoscale height which is greater or equal to lambda/2pi*n0 (here lambda is the characteristic radiation wavelength and n0 is the refractive index of the microresonator material). Overall, the microresonator possesses a broadband, small FSR, and accurately equidistant spectrum convenient for the generation of a broadband and low repetition rate optical frequency comb. It is shown that this comb can be generated by pumping with a cw laser, which radiation frequency matches a single axial eigenfrequency of the microresonator, or, alternatively, by p...

  2. Verbal behavior in Alzheimer disease patients: Analysis of phrase repetition

    Directory of Open Access Journals (Sweden)

    Juliana Francisca Cecato

    Full Text Available Abstract Language problems in the elderly with AD are due to the fact that deterioration occurs not only in semantic memory, but in a group of cognitive factors, evidenced by a deficiency in search strategies for linguistic information. Objectives: To evaluate phrase repetition in two cognitive tests, the MMSE and MoCA, in a group of Alzheimer disease patients (AD and normal controls. Methods: A Cross-sectional study was conducted involving 20 patients who sought medical assistance at a geriatric institute in Jundiaí, São Paulo. The subjects underwent a detailed clinical examination and neuropsychometric evaluation. All subjects with AD met DSM-IV and NINCDS-ADRDA criteria. Ten patients received a diagnosis of AD and 10 were healthy subjects, forming the control group (CG. Results: All participants correctly answered the phrase from the MMSE (phrase 1. The MoCA phrases (phrases 2 and 3 were correct in 80% and 90%, respectively in the CG and in 40% and 50%, respectively in the AD group. Conclusions: The MoCA test proved more effective in evaluating the echoic behavior in AD patients compared to the MMSE. The simpler phrase repetition task in the MMSE was found to be less sensitive in detecting mild language decline in AD patients.

  3. Effect of Airflows on Repetitive Nanosecond Volume Discharges

    Science.gov (United States)

    Tang, Jingfeng; Wei, Liqiu; Huo, Yuxin; Song, Jian; Yu, Daren; Zhang, Chaohai

    2016-03-01

    Atmospheric pressure discharges excited by repetitive nanosecond pulses have attracted significant attention for various applications. In this paper, a plate-plate discharge with airflows is excited by a repetitive nanosecond pulse generator. Under different experiment conditions, the applied voltages, discharge currents, and discharge images are recorded. The plasma images presented here indicate that the volume discharge modes vary with airflow speeds, and a diffuse and homogeneous volume discharge occurs at the speed of more than 35 m/s. The role of airflows provides different effects on the 2-stage pulse discharges. The 1st pulse currents nearly maintain consistency for different airflow speeds. However, the 2nd pulse current has a change trend of first decreasing and then rapidly increasing, and the value difference for 2nd pulse currents is about 20 A under different airflows. In addition, the experimental results are discussed according to the electrical parameters and discharge images. supported by National Natural Science Foundation of China (Nos. 51006027, 51437002, and 51477035)

  4. Rotated balance in humans due to repetitive rotational movement.

    Science.gov (United States)

    Zakynthinaki, M S; Milla, J Madera; De Durana, A López Diaz; Martínez, C A Cordente; Romo, G Rodríguez; Quintana, M Sillero; Molinuevo, J Sampedro

    2010-03-01

    We show how asymmetries in the movement patterns during the process of regaining balance after perturbation from quiet stance can be modeled by a set of coupled vector fields for the derivative with respect to time of the angles between the resultant ground reaction forces and the vertical in the anteroposterior and mediolateral directions. In our model, which is an adaption of the model of Stirling and Zakynthinaki (2004), the critical curve, defining the set of maximum angles one can lean to and still correct to regain balance, can be rotated and skewed so as to model the effects of a repetitive training of a rotational movement pattern. For the purposes of our study a rotation and a skew matrix is applied to the critical curve of the model. We present here a linear stability analysis of the modified model, as well as a fit of the model to experimental data of two characteristic "asymmetric" elite athletes and to a "symmetric" elite athlete for comparison. The new adapted model has many uses not just in sport but also in rehabilitation, as many work place injuries are caused by excessive repetition of unaligned and rotational movement patterns.

  5. Hemodynamic Profiles of Functional and Dysfunctional Forms of Repetitive Thinking.

    Science.gov (United States)

    Ottaviani, Cristina; Brosschot, Jos F; Lonigro, Antonia; Medea, Barbara; Van Diest, Ilse; Thayer, Julian F

    2017-04-01

    The ability of the human brain to escape the here and now (mind wandering) can take functional (problem solving) and dysfunctional (perseverative cognition) routes. Although it has been proposed that only the latter may act as a mediator of the relationship between stress and cardiovascular disease, both functional and dysfunctional forms of repetitive thinking have been associated with blood pressure (BP) reactivity of the same magnitude. However, a similar BP reactivity may be caused by different physiological determinants, which may differ in their risk for cardiovascular pathology. To examine the way (hemodynamic profile) and the extent (compensation deficit) to which total peripheral resistance and cardiac output compensate for each other in determining BP reactivity during functional and dysfunctional types of repetitive thinking. Fifty-six healthy participants randomly underwent a perseverative cognition, a mind wandering, and a problem solving induction, each followed by a 5-min recovery period while their cardiovascular parameters were continuously monitored. Perseverative cognition and problem solving (but not mind wandering) elicited BP increases of similar magnitude. However, perseverative cognition was characterized by a more vascular (versus myocardial) profile compared to mind wandering and problem solving. As a consequence, BP recovery was impaired after perseverative cognition compared to the other two conditions. Given that high vascular resistance and delayed recovery are the hallmarks of hypertension the results suggest a potential mechanism through which perseverative cognition may act as a mediator in the relationship between stress and risk for developing precursors to cardiovascular disease.

  6. Urine concentrations of repetitive doses of inhaled salbutamol

    DEFF Research Database (Denmark)

    Elers, J; Pedersen, Lars; Henninge, J

    2011-01-01

    We examined blood and urine concentrations of repetitive doses of inhaled salbutamol in relation to the existing cut-off value used in routine doping control. We compared the concentrations in asthmatics with regular use of beta2-agonists prior to study and healthy controls with no previous use...... of beta2-agonists. We enrolled 10 asthmatics and 10 controls in an open-label study in which subjects inhaled repetitive doses of 400 microgram salbutamol every second hour (total 1600 microgram), which is the permitted daily dose by the World Anti-Doping Agency (WADA). Blood samples were collected...... and the median ranged from 268 to 611 ng×mL (-1). No samples exceeded the WADA threshold value of 1000 ng×mL (-1) when corrected for the urine specific gravity. When not corrected one sample exceeded the cut-off value with urine concentration of 1082 ng×mL (-1). In conclusion we found no differences in blood...

  7. Multiple repetition time balanced steady-state free precession imaging.

    Science.gov (United States)

    Cukur, Tolga; Nishimura, Dwight G

    2009-07-01

    Although balanced steady-state free precession (bSSFP) imaging yields high signal-to-noise ratio (SNR) efficiency, the bright lipid signal is often undesirable. The bSSFP spectrum can be shaped to suppress the fat signal with scan-efficient alternating repetition time (ATR) bSSFP. However, the level of suppression is limited, and the pass-band is narrow due to its nonuniform shape. A multiple repetition time (TR) bSSFP scheme is proposed that creates a broad stop-band with a scan efficiency comparable with ATR-SSFP. Furthermore, the pass-band signal uniformity is improved, resulting in fewer shading/banding artifacts. When data acquisition occurs in more than a single TR within the multiple-TR period, the echoes can be combined to significantly improve the level of suppression. The signal characteristics of the proposed technique were compared with bSSFP and ATR-SSFP. The multiple-TR method generates identical contrast to bSSFP, and achieves up to an order of magnitude higher stop-band suppression than ATR-SSFP. In vivo studies at 1.5 T and 3 T demonstrate the superior fat-suppression performance of multiple-TR bSSFP.

  8. Final Report, Photocathodes for High Repetition Rate Light Sources

    Energy Technology Data Exchange (ETDEWEB)

    Ben-Zvi, Ilan [Stony Brook University

    2014-04-20

    This proposal brought together teams at Brookhaven National Laboratory (BNL), Lawrence Berkeley National Laboratory (LBNL) and Stony Brook University (SBU) to study photocathodes for high repetition rate light sources such as Free Electron Lasers (FEL) and Energy Recovery Linacs (ERL). The work done under this grant comprises a comprehensive program on critical aspects of the production of the electron beams needed for future user facilities. Our program pioneered in situ and in operando diagnostics for alkali antimonide growth. The focus is on development of photocathodes for high repetition rate Free Electron Lasers (FELs) and Energy Recovery Linacs (ERLs), including testing SRF photoguns, both normal-conducting and superconducting. Teams from BNL, LBNL and Stony Brook University (SBU) led this research, and coordinated their work over a range of topics. The work leveraged a robust infrastructure of existing facilities and the support was used for carrying out the research at these facilities. The program concentrated in three areas: a) Physics and chemistry of alkali-antimonide cathodes b) Development and testing of a diamond amplifier for photocathodes c) Tests of both cathodes in superconducting RF photoguns and copper RF photoguns

  9. Resistance to change of operant variation and repetition.

    Science.gov (United States)

    Doughty, A H; Lattal, K A

    2001-09-01

    A multiple chained schedule was used to compare the relative resistance to change of variable and fixed four-peck response sequences in pigeons. In one terminal link, a response sequence produced food only if it occurred infrequently relative to 15 other response sequences (vary). In the other terminal link, a single response sequence produced food (repeat). Identical variable-interval schedules operated in the initial links. During baseline, lower response rates generally occurred in the vary initial link, and similar response and reinforcement rates occurred in each terminal link. Resistance of responding to prefeeding and three rates of response-independent food delivered during the intercomponent intervals then was compared between components. During each disruption condition, initial- and terminal-link response rates generally were more resistant in the vary component than in the repeat component. During the response-independent food conditions, terminal-link response rates were more resistant than initial-link response rates in each component, but this did not occur during prefeeding. Variation (in vary) and repetition (in repeat) both decreased during the response-independent food conditions in the respective components, but with relatively greater disruption in repeat. These results extend earlier findings demonstrating that operant variation is more resistant to disruption than is operant repetition and suggest that theories of response strength, such as behavioral momentum theory, must consider factors other than reinforcement rate. The implications of the results for understanding operant response classes are discussed.

  10. Neuronal mechanisms and circuits underlying repetitive behaviors in mouse models of autism spectrum disorder.

    Science.gov (United States)

    Kim, Hyopil; Lim, Chae-Seok; Kaang, Bong-Kiun

    2016-01-20

    Autism spectrum disorder (ASD) refers to a broad spectrum of neurodevelopmental disorders characterized by three central behavioral symptoms: impaired social interaction, impaired social communication, and restricted and repetitive behaviors. However, the symptoms are heterogeneous among patients and a number of ASD mouse models have been generated containing mutations that mimic the mutations found in human patients with ASD. Each mouse model was found to display a unique set of repetitive behaviors. In this review, we summarize the repetitive behaviors of the ASD mouse models and variations found in their neural mechanisms including molecular and electrophysiological features. We also propose potential neuronal mechanisms underlying these repetitive behaviors, focusing on the role of the cortico-basal ganglia-thalamic circuits and brain regions associated with both social and repetitive behaviors. Further understanding of molecular and circuitry mechanisms of the repetitive behaviors associated with ASD is necessary to aid the development of effective treatments for these disorders.

  11. The informative value of type of repetition: Perceptual and conceptual fluency influences on judgments of truth.

    Science.gov (United States)

    Silva, Rita R; Garcia-Marques, Teresa; Reber, Rolf

    2017-05-01

    We contrast the effects of conceptual and perceptual fluency resulting from repetition in the truth effect. In Experiment 1, participants judged either verbatim or paraphrased repetitions, which reduce perceptual similarity to original statements. Judgments were made either immediately after the first exposure to the statements or after one week. Illusions of truth emerged for both types of repetition, with delay reducing both effects. In Experiment 2, participants judged verbatim and paraphrased repetitions with either the same or a contradictory meaning of original statements. In immediate judgments, illusions of truth emerged for repetitions with the same meaning and illusions of falseness for contradictory repetitions. In the delayed session, the illusion of falseness disappeared for contradictory statements. Results are discussed in terms of the contributions of recollection of stimulus details and of perceptual and conceptual fluency to illusions of truth at different time intervals and judgmental context conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Understanding work related musculoskeletal pain: does repetitive work cause stress symptoms?

    DEFF Research Database (Denmark)

    Bonde, J. P.; Mikkelsen, S.; Andersen, JH

    2005-01-01

    for development of regional pain in repetitive work, stress symptoms would likely be on the causal path. AIMS: To examine whether objective measures of repetitive monotonous work are related to occurrence and development of stress symptoms. METHODS: In 1994-95, 2033 unskilled workers with continuous repetitive...... work and 813 workers with varied work were enrolled. Measures of repetitiveness and force requirements were quantified using video observations to obtain individual exposure estimates. Stress symptoms were recorded at baseline and after approximately one, two, and three years by the Setterlind Stress...... Profile Inventory. RESULTS: Repetitive work, task cycle time, and quantified measures of repetitive upper extremity movements including force requirements were not related to occurrence of stress symptoms at baseline or development of stress symptoms during three years of follow up. CONCLUSIONS...

  13. rTMS of the occipital cortex abolishes Braille reading and repetition priming in blind subjects.

    Science.gov (United States)

    Kupers, R; Pappens, M; de Noordhout, A Maertens; Schoenen, J; Ptito, M; Fumal, A

    2007-02-27

    To study the functional involvement of the visual cortex in Braille reading, we applied repetitive transcranial magnetic stimulation (rTMS) over midoccipital (MOC) and primary somatosensory (SI) cortex in blind subjects. After rTMS of MOC, but not SI, subjects made significantly more errors and showed an abolishment of the improvement in reading speed following repetitive presentation of the same word list, suggesting a role of the visual cortex in repetition priming in the blind.

  14. Repetitive thinking and depressive symptoms in a normal population : responses to normal negative events

    OpenAIRE

    Larsen, Simen Mjøen

    2016-01-01

    Some theories view repetitive thinking as a maladaptive coping response that exacerbates depressive symptoms and explains the sex difference in depression. Other theories view repetitive thinking as the chief mechanism for solving complex social problems. A central theoretical assumption in evolutionary psychology is that psychological mechanisms are sensitive to modern cues to ancestral fitness-relevant contexts. The measures that are currently used to probe repetitive thinking does not refl...

  15. Peripheral and central changes combine to induce motor behavioral deficits in a moderate repetition task

    OpenAIRE

    Coq, Jacques-Olivier; Barr, Ann E.; Strata, Fabrizio; Russier, Michael; Kietrys, David M; Merzenich, Michael M.; Byl, Nancy N; Barbe, Mary F

    2009-01-01

    Repetitive motion disorders, such as carpal tunnel syndrome and focal hand dystonia, can be associated with tasks that require prolonged, repetitive behaviors. Previous studies using animal models of repetitive motion have correlated cortical neuroplastic changes or peripheral tissue inflammation with fine motor performance. However, the possibility that both peripheral and central mechanisms coexist with altered motor performance has not been studied. In this study, we investigated the relat...

  16. PCR amplification of repetitive sequences as a possible approach in relative species quantification

    DEFF Research Database (Denmark)

    Ballin, Nicolai Zederkopff; Vogensen, Finn Kvist; Karlsson, Anders H

    2012-01-01

    in binary mixtures. PCR LUX primers were designed that amplify repetitive and single copy sequences to establish the species dependent number (constants) (SDC) of amplified repetitive sequences per genome. The SDCs and data from amplification of repetitive sequences were tested for their applicability...... to relatively quantify the amount of chicken DNA in a binary mixture of chicken DNA and pig DNA. However, the designed PCR primers lack the specificity required for regulatory species control....

  17. Relationship between repetitive firing and afterhyperpolarizations in human neocortical neurons.

    Science.gov (United States)

    Lorenzon, N M; Foehring, R C

    1992-02-01

    1. Human neocortical neurons fire repetitively in response to long depolarizing current injections. The slope of the relationship between average firing frequency and injected current (f-I slope) was linear or bilinear in these cells. The mean steady-state f-I slope (average of the last 500 ms of a 1-s firing episode) was 57.8 Hz/nA. The instantaneous firing rate decreased with time during a 1-s constant-current injection (spike frequency adaptation). Also, human neurons exhibited habituation in response to a 1-s current stimulus repeated every 2 s. 2. Afterhyperpolarizations (AHPs) reflect the active ionic conductances after action potentials. We studied AHPs with the use of intracellular recordings and pharmacological manipulations in the in vitro slice preparation to 1) gain insight into the ionic mechanisms underlying the AHPs and 2) elucidate the role that the underlying currents play in the functional behavior of human cortical neurons. 3. We have classified three AHPs in human neocortical neurons on the basis of their time courses: fast, medium, and slow. The amplitude of the AHPs was dependent on stimulus intensity and duration, number and frequency of spikes, and membrane potential. 4. The fast AHP had a reversal potential of -65 mV and was eliminated in extracellular Co2+, tetraethylammonium (TEA) or 4-aminopyridine, and intracellular TEA or CsCl. These manipulations also caused an increase in spike width. 5. The medium AHP had a reversal potential of -90 to -93 mV (22-24 mV hyperpolarized from mean resting potential). This AHP was reduced by Co2+, apamin, tubocurare, muscarine, norepinephrine (NE), and serotonin (5-HT). Pharmacological manipulations suggest that the medium AHP is produced in part by 1) a Ca-dependent K+ current and 2) a time-dependent anomalous rectifier (IH). 6. The slow AHP reversed at -83 to -87 mV (14-18 mV hyperpolarized from mean resting potential). This AHP was diminished by Co2+, muscarine, NE, and 5-HT. The pharmacology of the

  18. Establishing the baseline level of repetitive element expression in the human cortex

    National Research Council Canada - National Science Library

    Tyekucheva, Svitlana; Yolken, Robert H; McCombie, W Richard; Parla, Jennifer; Kramer, Melissa; Wheelan, Sarah J; Sabunciyan, Sarven

    2011-01-01

    .... Hence, we performed whole transcriptome sequencing to investigate the expression of repetitive elements in human frontal cortex using postmortem tissue obtained from the Stanley Medical Research Institute...

  19. Movement repetitions in physical and occupational therapy during spinal cord injury rehabilitation.

    Science.gov (United States)

    Zbogar, D; Eng, J J; Miller, W C; Krassioukov, A V; Verrier, M C

    2017-02-01

    Longitudinal observational study. To quantify the amount of upper- and lower-extremity movement repetitions (that is, voluntary movements as part of a functional task or specific motion) occurring during inpatient spinal cord injury (SCI), physical (PT) and occupational therapy (OT), and examine changes over the inpatient rehabilitation stay. Two stand-alone inpatient SCI rehabilitation centers. Participants: A total of 103 patients were recruited through consecutive admissions to SCI rehabilitation. Trained assistants observed therapy sessions and obtained clinical outcome measures in the second week following admission and in the second to last week before discharge. PT and OT time, upper- and lower-extremity repetitions and changes in these outcomes over the course of rehabilitation stay. We observed 561 PT and 347 OT sessions. Therapeutic time comprised two-thirds of total therapy time. Summed over PT and OT, the median upper-extremity repetitions in patients with paraplegia were 7 repetitions and in patients with tetraplegia, 42 repetitions. Lower-extremity repetitions and steps primarily occurred in ambulatory patients and amounted to 218 and 115, respectively (summed over PT and OT sessions at discharge). Wilcoxon-signed rank tests revealed that most repetition variables did not change significantly over the inpatient rehabilitation stay. In contrast, clinical outcomes for the arm and leg improved over this time period. Repetitions of upper- and lower-extremity movements are markedly low during PT and OT sessions. Despite improvements in clinical outcomes, there was no significant increase in movement repetitions over the course of inpatient rehabilitation stay.

  20. Clinical application of gradient echo sequences with prolonged repetition times

    Energy Technology Data Exchange (ETDEWEB)

    Tiling, R.; Fink, U.; Deimling, M.; Bauer, W.M.; Yousry, T.; Krauss, B.

    1988-09-01

    Studies designed to optimise image contrasts of gradient echo sequences showed, that especially repetition times between 250 and 500 ms in combination with adequate echo times and flip angles provide new image contrasts. The clinical purpose of gradient echo sequences with longer TR was systematically evaluated in 450 patients. A major advantage of GE sequences was the low signal intensity of fat and bone tissue. On the other hand differnt pathologic changes showed a high signal intensity in comparison to T/sub 2/ weighted spin echo sequences as well. With the possibility of multiple slices GE sequences were of outstanding diagnostic value especially in MR of soft tissue and of the musculoskeletal system. T/sub 2/ weighted SE sequences provided no additional informations and could therefore be omitted in a great number of examinations.

  1. Repetitive Bunches from RF-Photo Gun Radiate Coherently

    CERN Document Server

    Van der Geer, C A J; Van der Geer, S B

    2004-01-01

    We consider to feed the laser wake field accelerator of the alpha-X project by a train of low charge pancake electron bunches to reduce undesired expansion due to space-charge forces. To this purpose the photo excitation laser of the rf-injector is split into a train of sub-pulses, such that each of the produced electron bunches falls into a successive ponderomotive well of the plasma accelerator. This way the total accelerated charge is not reduced. The repetitive photo gun can be tested, at low energy, by connecting it directly to the undulator and monitoring the radiation. The assertions are based on the results of new GPT simulations.

  2. Distribution of repetitions of ancestors in genealogical trees

    Science.gov (United States)

    Derrida, Bernard; Manrubia, Susanna C.; Zanette, Damián H.

    2000-06-01

    We calculate the probability distribution of repetitions of ancestors in a genealogical tree for simple neutral models of a closed population with sexual reproduction and non-overlapping generations. Each ancestor at generation g in the past has a weight w which is (up to a normalization) the number of times this ancestor appears in the genealogical tree of an individual at present. The distribution Pg( w) of these weights reaches a stationary shape P∞( w), for large g, i.e., for a large number of generations back in the past. For small w, P ∞(w) is a power law ( P∞( w)∼ wβ), with a non-trivial exponent β which can be computed exactly using a standard procedure of the renormalization group approach. Some extensions of the model are discussed and the effect of these variants on the shape of P∞( w) are analysed.

  3. Repetitive elements dynamics in cell identity programming, maintenance and disease

    KAUST Repository

    Bodega, Beatrice

    2014-12-01

    The days of \\'junk DNA\\' seem to be over. The rapid progress of genomics technologies has been unveiling unexpected mechanisms by which repetitive DNA and in particular transposable elements (TEs) have evolved, becoming key issues in understanding genome structure and function. Indeed, rather than \\'parasites\\', recent findings strongly suggest that TEs may have a positive function by contributing to tissue specific transcriptional programs, in particular as enhancer-like elements and/or modules for regulation of higher order chromatin structure. Further, it appears that during development and aging genomes experience several waves of TEs activation, and this contributes to individual genome shaping during lifetime. Interestingly, TEs activity is major target of epigenomic regulation. These findings are shedding new light on the genome-phenotype relationship and set the premises to help to explain complex disease manifestation, as consequence of TEs activity deregulation.

  4. RN-BSN curricula: designed for transition, not repetition.

    Science.gov (United States)

    Allen, Patricia E; Armstrong, Myrna L

    2013-01-01

    Combined efforts of professional mandates, employer preferences for increased educational levels of staff registered nurses (RNs), Magnet's higher environmental ratings, the Institute of Medicine report, and Aiken's (2003, 2008, & 2011) clinical research outcomes have spawn renewed attention for RN-baccalaureate degree of science in nursing (BSN) education. Yet, nationally, only 21.6% of associate degree nurses are continuing their education (Health Resources and Services Administration, 2010). Designing programs with the student as the center, where student/faculty engagement is the goal, has enabled one school of nursing to develop a quality on-line RN-to-BSN program. Core values of the program reveal a faculty who is committed to development of education to transition the associate degree and/or diploma graduate to professional nursing practice without repetition of content and learning activities.

  5. Repetition blindness for natural images of objects with viewpoint changes

    Directory of Open Access Journals (Sweden)

    Stephane eBuffat

    2013-01-01

    Full Text Available When stimuli are repeated in a rapid serial visual presentation (RSVP, observers sometimes fail to report the second occurrence of a target. This phenomenon is referred to as repetition blindness (RB. We report an RSVP experiment with photographs in which we manipulated object viewpoints between the first and second occurrences of a target (0-, 45-, or 90-degree changes, and spatial frequency content. Natural images were spatially filtered to produce low, medium, or high spatial-frequency stimuli. RB was observed for all filtering conditions. Surprisingly, for full-spectrum images, RB increased significantly as the viewpoint reached 90 degrees. For filtered images, a similar pattern of results was found for all conditions except for medium spatial-frequency stimuli. These findings suggest that object recognition in RSVP are subtended by viewpoint-specific representations for all spatial frequencies except medium ones.

  6. Simple filtered repetitively pulsed vacuum arc plasma source

    Science.gov (United States)

    Chekh, Yu.; Zhirkov, I. S.; Delplancke-Ogletree, M. P.

    2010-02-01

    A very simple design of cathodic filtered vacuum arc plasma source is proposed. The source without filter has only four components and none of them require precise machining. The source operates in a repetitively pulsed regime, and for laboratory experiments it can be used without water cooling. Despite the simple construction, the source provides high ion current at the filter outlet reaching 2.5% of 400 A arc current, revealing stable operation in a wide pressure range from high vacuum to oxygen pressure up to more than 10-2 mbar. There is no need in complicated power supply system for this plasma source, only one power supply can be used to ignite the arc, to provide the current for the arc itself, to generate the magnetic field in the filter, and provide its positive electric biasing without any additional high power resistance.

  7. Resistive Wall Heating of the Undulator in High Repetition Rate

    Energy Technology Data Exchange (ETDEWEB)

    Qiang, J; Corlett, J; Emma, P; Wu, J

    2012-05-20

    In next generation high repetition rate FELs, beam energy loss due to resistive wall wakefields will produce significant amount of heat. The heat load for a superconducting undulator (operating at low temperature), must be removed and will be expensive to remove. In this paper, we study this effect in an undulator proposed for a Next Generation Light Source (NGLS) at LBNL. We benchmark our calculations with measurements at the LCLS and carry out detailed parameter studies using beam from a start-to-end simulation. Our preliminarym results suggest that the heat load in the undulator is about 2 W/m or lower with an aperture size of 6 mm for nominal NGLS preliminary design parameters.

  8. A high repetition rate XUV seeding source for FLASH2

    Energy Technology Data Exchange (ETDEWEB)

    Willner, Arik

    2012-05-15

    Improved performance of free-electron laser (FEL) light sources in terms of timing stability, pulse shape and spectral properties of the amplified FEL pulses is of interest in material science, the fields of ultrafast dynamics, biology, chemistry and even special branches in industry. A promising scheme for such an improvement is direct seeding with high harmonic generation (HHG) in a noble gas target. A free-electron laser seeded by an external extreme ultraviolet (XUV) source is planned for FLASH2 at DESY in Hamburg. The requirements for the XUV/soft X-ray source can be summarized as follows: A repetition rate of at least 100 kHz in a 10 Hz burst is needed at variable wavelengths from 10 to 40 nm and pulse energies of several nJ within a single laser harmonic. This application requires a laser amplifier system with exceptional parameters, mJ-level pulse energy, 10-15 fs pulse duration at 100 kHz (1 MHz) burst repetition rate. A new optical parametric chirped-pulse amplification (OPCPA) system is under development in order to meet these requirements, and very promising results have been achieved in the last three years. In parallel to this development, a new HHG concept is necessary to sustain high average power of the driving laser system and to generate harmonics with high conversion efficiencies. Currently, the highest conversion efficiency with HHG has been demonstrated using gas-filled capillary targets. For our application, only a free-jet target can be used for HHG, in order to overcome damage threshold limitations of HHG target optics at a high repetition rate. A novel dual-gas multijet gas target has been developed and first experiments show remarkable control of the degree of phase matching forming the basis for improved control of the harmonic photon flux and the XUV pulse characteristics. The basic idea behind the dual-gas concept is the insertion of matching zones in between multiple HHG sources. These matching sections are filled with hydrogen which

  9. Intrinsic and extrinsic motivation for stereotypic and repetitive behavior.

    Science.gov (United States)

    Joosten, Annette V; Bundy, Anita C; Einfeld, Stewart L

    2009-03-01

    This study provides evidence for intrinsic and extrinsic motivators for stereotypical and repetitive behavior in children with autism and intellectual disability and children with intellectual disability alone. We modified the Motivation Assessment Scale (MAS) (1988b); dividing it into intrinsic and extrinsic measures and adding items to assess anxiety as an intrinsic motivator. Rasch analysis of data from 279 MASs (74 children) revealed that the items formed two unidimensional scales. Anxiety was a more likely intrinsic motivator than sensory seeking for children with dual diagnoses; the reverse was true for children with intellectual disability only. Escape and gaining a tangible object were the most common extrinsic motivators for those with dual diagnoses and attention and escape for children with intellectual disability.

  10. Pancreatic Cancer: 80 Years of Surgery—Percentage and Repetitions

    Directory of Open Access Journals (Sweden)

    Birgir Gudjonsson

    2016-01-01

    Full Text Available Objective. The incidence of pancreatic cancer is estimated to be 48,960 in 2015 in the US and projected to become the second and third leading causes of cancer-related deaths by 2030. The mean costs in 2015 may be assumed to be $79,800 per patient and for each resection $164,100. Attempt is made to evaluate the results over the last 80 years, the number of survivors, and the overall survival percentage. Methods. Altogether 1230 papers have been found which deal with resections and reveal survival information. Only 621 of these report 5-year survivors. Reservation about surgery was first expressed in 1964 and five-year survival of nonresected survivors is well documented. Results. The survival percentage depends not only on the number of survivors but also on the subset from which it is calculated. Since the 1980s the papers have mainly reported the number of resections and survival as actuarial percentages, with or without the actual number of survivors being reported. The actuarial percentage is on average 2.75 higher. Detailed information on the original group (TN, number of resections, and actual number of survivors is reported in only 10.6% of the papers. Repetition occurs when the patients from a certain year are reported several times from the same institution or include survivors from many institutions or countries. Each 5-year survivor may be reported several times. Conclusion. Assuming a 10% resection rate and correcting for repetitions and the life table percentage the overall actual survival rate is hardly more than 0.3%.

  11. Repetition priming in selective attention: A TVA analysis.

    Science.gov (United States)

    Ásgeirsson, Árni Gunnar; Kristjánsson, Árni; Bundesen, Claus

    2015-09-01

    Current behavior is influenced by events in the recent past. In visual attention, this is expressed in many variations of priming effects. Here, we investigate color priming in a brief exposure digit-recognition task. Observers performed a masked odd-one-out singleton recognition task where the target-color either repeated or changed between subsequent trials. Performance was measured by recognition accuracy over exposure durations. The purpose of the study was to replicate earlier findings of perceptual priming in brief displays and to model those results based on a Theory of Visual Attention (TVA; Bundesen, 1990). We tested 4 different definitions of a generic TVA-model and assessed their explanatory power. Our hypothesis was that priming effects could be explained by selective mechanisms, and that target-color repetitions would only affect the selectivity parameter (α) of our models. Repeating target colors enhanced performance for all 12 observers. As predicted, this was only true under conditions that required selection of a target among distractors, but not when a target was presented alone. Model fits by TVA were obtained with a trial-by-trial maximum likelihood estimation procedure that estimated 4-15 free parameters, depending on the particular model. We draw two main conclusions. Color priming can be modeled simply as a change in selectivity between conditions of repetition or swap of target color. Depending on the desired resolution of analysis; priming can accurately be modeled by a simple four parameter model, where VSTM capacity and spatial biases of attention are ignored, or more fine-grained by a 10 parameter model that takes these aspects into account. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Dissecting the functional anatomy of auditory word repetition

    Directory of Open Access Journals (Sweden)

    Thomas Matthew Hadley Hope

    2014-05-01

    Full Text Available Auditory word repetition involves many different brain regions, whose functions are still far from fully understood. Here, we use a single, multi-factorial, within-subjects fMRI design to identify those regions, and to functionally distinguish the multiple linguistic and non-linguistic processing areas that are all involved in repeating back heard words. The study compared: (1 auditory to visual inputs; (2 phonological to non-phonological inputs; (3 semantic to non-semantic inputs; and (4 speech production to finger-press responses. The stimuli included words (semantic and phonological inputs, pseudowords (phonological input, pictures and sounds of animals or objects (semantic input, and coloured patterns and hums (non-semantic and non-phonological. The speech production tasks involved auditory repetition, reading and naming while the finger press tasks involved one-back matching.The results from the main effects and interactions were compared to predictions from a previously reported functional anatomical model of language based on a meta-analysis of many different neuroimaging experiments. Although many findings from the current experiment replicated those predicted, our within-subject design also revealed novel results by providing sufficient anatomical precision to distinguish several different regions within: (1 the anterior insula (a dorsal region involved in both covert and overt speech production, and a more ventral region involved in overt speech only; (2 the pars orbitalis (with distinct sub-regions responding to phonological and semantic processing; (3 the anterior cingulate and SMA (whose subregions show differential sensitivity to speech and finger press responses; and (4 the cerebellum (with distinct regions for semantic processing, speech production and domain general processing. We also dissociated four different types of phonological effects in, respectively, the left superior temporal sulcus, left putamen, left ventral premoto

  13. Repetitive Pediatric Anesthesia in a Non-Hospital Setting

    Energy Technology Data Exchange (ETDEWEB)

    Buchsbaum, Jeffrey C., E-mail: jbuchsba@iupui.edu [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana (United States); Indiana University Health Proton Therapy Center, Bloomington, Indiana (United States); McMullen, Kevin P.; Douglas, James G. [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana (United States); Indiana University Health Proton Therapy Center, Bloomington, Indiana (United States); Jackson, Jeffrey L.; Simoneaux, R. Victor; Hines, Matthew; Bratton, Jennifer; Kerstiens, John [Indiana University Health Proton Therapy Center, Bloomington, Indiana (United States); Johnstone, Peter A.S. [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana (United States); Indiana University Health Proton Therapy Center, Bloomington, Indiana (United States)

    2013-04-01

    Purpose: Repetitive sedation/anesthesia (S/A) for children receiving fractionated radiation therapy requires induction and recovery daily for several weeks. In the vast majority of cases, this is accomplished in an academic center with direct access to pediatric faculty and facilities in case of an emergency. Proton radiation therapy centers are more frequently free-standing facilities at some distance from specialized pediatric care. This poses a potential dilemma in the case of children requiring anesthesia. Methods and Materials: The records of the Indiana University Health Proton Therapy Center were reviewed for patients requiring anesthesia during proton beam therapy (PBT) between June 1, 2008, and April 12, 2012. Results: A total of 138 children received daily anesthesia during this period. A median of 30 fractions (range, 1-49) was delivered over a median of 43 days (range, 1-74) for a total of 4045 sedation/anesthesia procedures. Three events (0.0074%) occurred, 1 fall from a gurney during anesthesia recovery and 2 aspiration events requiring emergency department evaluation. All 3 children did well. One aspiration patient needed admission to the hospital and mechanical ventilation support. The other patient returned the next day for treatment without issue. The patient who fell was not injured. No patient required cessation of therapy. Conclusions: This is the largest reported series of repetitive pediatric anesthesia in radiation therapy, and the only available data from the proton environment. Strict adherence to rigorous protocols and a well-trained team can safely deliver daily sedation/anesthesia in free-standing proton centers.

  14. Hemispheric Asymmetries in Repetition Enhancement and Suppression Effects in the Newborn Brain.

    Directory of Open Access Journals (Sweden)

    Camillia Bouchon

    Full Text Available The repeated presentation of stimuli typically attenuates neural responses (repetition suppression or, less commonly, increases them (repetition enhancement when stimuli are highly complex, degraded or presented under noisy conditions. In adult functional neuroimaging research, these repetition effects are considered as neural correlates of habituation. The development and respective functional significance of these effects in infancy remain largely unknown.This study investigates repetition effects in newborns using functional near-infrared spectroscopy, and specifically the role of stimulus complexity in evoking a repetition enhancement vs. a repetition suppression response, following up on Gervain et al. (2008. In that study, abstract rule-learning was found at birth in cortical areas specific to speech processing, as evidenced by a left-lateralized repetition enhancement of the hemodynamic response to highly variable speech sequences conforming to a repetition-based ABB artificial grammar, but not to a random ABC grammar.Here, the same paradigm was used to investigate how simpler stimuli (12 different sequences per condition as opposed to 140, and simpler presentation conditions (blocked rather than interleaved would influence repetition effects at birth.Results revealed that the two grammars elicited different dynamics in the two hemispheres. In left fronto-temporal areas, we reproduce the early perceptual discrimination of the two grammars, with ABB giving rise to a greater response at the beginning of the experiment than ABC. In addition, the ABC grammar evoked a repetition enhancement effect over time, whereas a stable response was found for the ABB grammar. Right fronto-temporal areas showed neither initial discrimination, nor change over time to either pattern.Taken together with Gervain et al. (2008, this is the first evidence that manipulating methodological factors influences the presence or absence of neural repetition enhancement

  15. Identification of two new repetitive elements and chromosomal mapping of repetitive DNA sequences in the fish Gymnothorax unicolor (Anguilliformes: Muraenidae

    Directory of Open Access Journals (Sweden)

    E. Coluccia

    2011-05-01

    Full Text Available Muraenidae is a species-rich family, with relationships among genera and species and taxonomy that have not been completely clarified. Few cytogenetic studies have been conducted on this family, and all of them showed the same diploid chromosome number (2n=42 but with conspicuous karyotypic variation among species. The Mediterranean moray eel Gymnothorax unicolor was previously cytogenetically studied using classical techniques that allowed the characterization of its karyotype structure and the constitutive heterochromatin and argyrophilic nucleolar organizer regions (Ag-NORs distribution pattern. In the present study, we describe two new repetitive elements (called GuMboI and GuDdeI obtained from restricted genomic DNA of G. unicolor that were characterized by Southern blot and physically localized by in situ hybridization on metaphase chromosomes. As they are highly repetitive DNA sequences, they map in heterochromatic regions. However, while GuDdeI was localized in the centromeric regions, the GuMboI fraction was distributed on some centromeres and was co-localized with the nucleolus organizer region (NOR. Comparative analysis with other Mediterranean species such as Muraena helena pointed out that these DNA fractions are species-specific and could potentially be used for species discrimination. As a new contribution to the karyotype of this species, we found that the major ribosomal genes are localized on acrocentric chromosome 9 and that the telomeres of each chromosome are composed of a tandem repeat derived from a poly-TTAGGG DNA sequence, as it occurs in most vertebrate species. The results obtained add new information useful in comparative genomics at the chromosomal level and contribute to the cytogenetic knowledge regarding this fish family, which has not been extensively studied.

  16. The effects of high resistance-few repetitions and low resistance-high repetitions resistance training on climbing performance.

    Science.gov (United States)

    Hermans, Espen; Andersen, Vidar; Saeterbakken, Atle Hole

    2017-05-01

    The aim of the study was to compare the effects of different strength training intensities on climbing performance, climbing-specific tests and a general strength test. Thirty lower grade and intermediate-level climbers participated in a 10-week training programme. The participants were randomized into three groups: high resistance-few repetitions training groups (HR-FR), low resistance-high repetitions training groups (LR-HR) and a control group (CON) which continued climbing/training as usual. Post-testing results demonstrated statistical tendencies for climbing performance improvements in the HR-FR and LR-HR (p = 0.088-0.090, effect size = 0.55-0.73), but no differences were observed between the groups (p = 0.950). For the climbing-specific tests, no differences were observed between the groups (p = 0.507-1.000), but the HR-FR and LR-HR improved their time in both Dead-hang (p = 0.004-0.026) and Bent-arm hang (p training groups reduced their climbing sessions during the intervention compared to the CON group (p = 0.057-0.074). In conclusion, HR-FR and LR-HR training programmes demonstrated an 11% and 12% non-significant improvement in climbing performance despite a 50% reduction in climbing sessions, but improved the results in strength and climbing-specific tests. None of the training intensities was superior compared to the others.

  17. The Action Plan Against Repetitive Work - An Industrial Relation Strategy for Improving the Working Environment

    DEFF Research Database (Denmark)

    Hasle, Peter; Møller, Niels

    2001-01-01

    The Danish Action Plan against Repetitive Work is presented and discussed as a possible new strategy for regulating repetitive work as well as other complicated working environment problems. The article is based on an empirical evaluation ot the Action Plan. The asseessment of the Action Plan ind...... and industrial relation agreements can be used to regulate other working environment problems....

  18. Nonword Repetition and Phoneme Elision in Adults Who Do and Do Not Stutter

    Science.gov (United States)

    Byrd, Courtney T.; Vallely, Megann; Anderson, Julie D.; Sussman, Harvey

    2012-01-01

    The purpose of the present study was to explore the phonological working memory of adults who stutter through the use of a non-word repetition and a phoneme elision task. Participants were 14 adults who stutter (M = 28 years) and 14 age/gender matched adults who do not stutter (M = 28 years). For the non-word repetition task, the participants had…

  19. The Function of Repeating: The Relation between Word Class and Repetition Type in Developmental Stuttering

    Science.gov (United States)

    Buhr, Anthony P.; Jones, Robin M.; Conture, Edward G.; Kelly, Ellen M.

    2016-01-01

    Background: It is already known that preschool-age children who stutter (CWS) tend to stutter on function words at the beginning of sentences. It is also known that phonological errors potentially resulting in part-word repetitions tend to occur on content words. However, the precise relation between word class and repetition type in preschool-age…

  20. On the Road to Science Literacy: Building Confidence and Competency in Technical Language through Choral Repetition

    Science.gov (United States)

    Hohenshell, Liesl M.; Woller, Michael J.; Sherlock, Wallace

    2013-01-01

    In order to be successful, students must acquire the language of science for both oral and written communication. In this article we examine an oral language learning technique called choral repetition for its role in building literacy in the context of an animal physiology course. For 3 weeks, the instructor conducted choral repetitions of nine…

  1. Functional dissociations in top-down control dependent neural repetition priming.

    NARCIS (Netherlands)

    Klaver, P.; Schnaidt, M.; Fell, J.; Ruhlmann, J.; Elger, C.E.; Fernandez, G.

    2007-01-01

    Little is known about the neural mechanisms underlying top-down control of repetition priming. Here, we use functional brain imaging to investigate these mechanisms. Study and repetition tasks used a natural/man-made forced choice task. In the study phase subjects were required to respond to either

  2. Task Repetition Effects on L1 Use in EFL Child Task-Based Interaction

    Science.gov (United States)

    Azkarai, Agurtzane; García Mayo, María del Pilar

    2017-01-01

    Research has shown that tasks provide second language (L2) learners with many opportunities to learn the L2. Task repetition has been claimed to benefit L2 learning since familiarity with procedure and/or content gives learners the chance to focus on more specific aspects of language. Most research on task repetition has focused on adult…

  3. Repetition suppression and expectation suppression are dissociable in time in early auditory evoked fields.

    Science.gov (United States)

    Todorovic, Ana; de Lange, Floris P

    2012-09-26

    Repetition of a stimulus, as well as valid expectation that a stimulus will occur, both attenuate the neural response to it. These effects, repetition suppression and expectation suppression, are typically confounded in paradigms in which the nonrepeated stimulus is also relatively rare (e.g., in oddball blocks of mismatch negativity paradigms, or in repetition suppression paradigms with multiple repetitions before an alternation). However, recent hierarchical models of sensory processing inspire the hypothesis that the two might be separable in time, with repetition suppression occurring earlier, as a consequence of local transition probabilities, and suppression by expectation occurring later, as a consequence of learnt statistical regularities. Here we test this hypothesis in an auditory experiment by orthogonally manipulating stimulus repetition and stimulus expectation and, using magnetoencephalography, measuring the neural response over time in human subjects. We found that stimulus repetition (but not stimulus expectation) attenuates the early auditory response (40-60 ms), while stimulus expectation (but not stimulus repetition) attenuates the subsequent, intermediate stage of auditory processing (100-200 ms). These findings are well in line with hierarchical predictive coding models, which posit sequential stages of prediction error resolution, contingent on the level at which the hypothesis is generated.

  4. Subcategories of Restricted and Repetitive Behaviors in Children with Autism Spectrum Disorders

    Science.gov (United States)

    Bishop, Somer L.; Hus, Vanessa; Duncan, Amie; Huerta, Marisela; Gotham, Katherine; Pickles, Andrew; Kreiger, Abba; Buja, Andreas; Lund, Sabata; Lord, Catherine

    2013-01-01

    Research suggests that restricted and repetitive behaviors (RRBs) can be subdivided into Repetitive Sensory Motor (RSM) and Insistence on Sameness (IS) behaviors. However, because the majority of previous studies have used the Autism Diagnostic Interview-Revised (ADI-R), it is not clear whether these subcategories reflect the actual organization…

  5. Measuring Repetitive Behaviors as a Treatment Endpoint in Youth with Autism Spectrum Disorder

    Science.gov (United States)

    Scahill, Lawrence; Aman, Michael G.; Lecavalier, Luc; Halladay, Alycia K.; Bishop, Somer L.; Bodfish, James W.; Grondhuis, Sabrina; Jones, Nancy; Horrigan, Joseph P.; Cook, Edwin H.; Handen, Benjamin L.; King, Bryan H.; Pearson, Deborah A.; McCracken, James T.; Sullivan, Katherine Anne; Dawson, Geraldine

    2015-01-01

    Restricted interests and repetitive behaviors vary widely in type, frequency, and intensity among children and adolescents with autism spectrum disorder. They can be stigmatizing and interfere with more constructive activities. Accordingly, restricted interests and repetitive behaviors may be a target of intervention. Several standardized…

  6. Brief Report: Repetitive Behaviours in Greek Individuals with Autism Spectrum Disorder

    Science.gov (United States)

    Georgiades, Stelios; Papageorgiou, Vaya; Anagnostou, Evdokia

    2010-01-01

    The main objective of this study was to examine the factor structure of restricted repetitive behaviours (RRBs) in a sample of 205 Greek individuals with Autism Spectrum Disorder (ASD), using the Repetitive Behavior Scale-Revised (RBS-R). Results show that the structure of RRBs in this Greek sample can be described using a 2-factor solution. The…

  7. The Repetitive Behavior Scale-Revised: Independent Validation in Individuals with Autism Spectrum Disorders

    Science.gov (United States)

    Lam, Kristen S. L.; Aman, Michael G.

    2007-01-01

    A key feature of autism is restricted repetitive behavior (RRB). Despite the significance of RRBs, little is known about their phenomenology, assessment, and treatment. The Repetitive Behavior Scale-Revised (RBS-R) is a recently-developed questionnaire that captures the breadth of RRB in autism. To validate the RBS-R in an independent sample, we…

  8. Motor Control and Nonword Repetition in Specific Working Memory Impairment and SLI

    Science.gov (United States)

    Archibald, Lisa M. D.; Joanisse, Marc F.; Munson, Benjamin

    2013-01-01

    Purpose: Debate around the underlying cognitive factors leading to poor performance in the repetition of nonwords by children with developmental impairments in language has centered around phonological short-term memory, lexical knowledge, and other factors. This study examines the impact of motor control demands on nonword repetition in groups of…

  9. Repetition rate continuously tunable 10-GHz picosecond mode-locked fiber ring laser

    Institute of Scientific and Technical Information of China (English)

    Fang Wan; Ziyu Wang

    2006-01-01

    A couple of simple-structure phase modulators were used in active mode-locked fiber laser to implement repetition rate continuous tuning. The laser produces pulse as short as 5.7 ps whose repetition rate tuning can cover the spacing of the adjoining order mode-locking frequencies.

  10. Molecular characterization and physical localization of highly repetitive DNA sequences from Brazilian Alstroemeria species

    NARCIS (Netherlands)

    Kuipers, A.G.J.; Kamstra, S.A.; Jeu, de M.J.; Jacobsen, E.

    2002-01-01

    Highly repetitive DNA sequences were isolated from genomic DNA libraries of Alstroemeria psittacina and A. inodora. Among the repetitive sequences that were isolated, tandem repeats as well as dispersed repeats could be discerned. The tandem repeats belonged to a family of interlinked Sau3A subfragm

  11. Frequency Adaptive Repetitive Control of Grid-Tied Three-Phase PV Inverters

    DEFF Research Database (Denmark)

    Zhou, Keliang; Yang, Yongheng; Blaabjerg, Frede

    2016-01-01

    Repetitive control offers an accurate current control scheme for grid-tied converters to feed high quality sinusoidal current into the grid. However, with grid frequency being treated as a constant value, conventional repetitive controller fail to produce high quality feeding current...

  12. Motor Control and Nonword Repetition in Specific Working Memory Impairment and SLI

    Science.gov (United States)

    Archibald, Lisa M. D.; Joanisse, Marc F.; Munson, Benjamin

    2013-01-01

    Purpose: Debate around the underlying cognitive factors leading to poor performance in the repetition of nonwords by children with developmental impairments in language has centered around phonological short-term memory, lexical knowledge, and other factors. This study examines the impact of motor control demands on nonword repetition in groups of…

  13. Topic Repetitiveness after Traumatic Brain Injury: An Emergent, Jointly Managed Behaviour

    Science.gov (United States)

    Body, Richard; Parker, Mark

    2005-01-01

    Topic repetitiveness is a common component of pragmatic impairment and a powerful contributor to social exclusion. Despite this, description, characterization and intervention remain underdeveloped. This article explores the nature of repetitiveness in traumatic brain injury (TBI). A case study of one individual after TBI provides the basis for a…

  14. Changes of the Prefrontal EEG (Electroencephalogram) Activities According to the Repetition of Audio-Visual Learning.

    Science.gov (United States)

    Kim, Yong-Jin; Chang, Nam-Kee

    2001-01-01

    Investigates the changes of neuronal response according to a four time repetition of audio-visual learning. Obtains EEG data from the prefrontal (Fp1, Fp2) lobe from 20 subjects at the 8th grade level. Concludes that the habituation of neuronal response shows up in repetitive audio-visual learning and brain hemisphericity can be changed by…

  15. On the Road to Science Literacy: Building Confidence and Competency in Technical Language through Choral Repetition

    Science.gov (United States)

    Hohenshell, Liesl M.; Woller, Michael J.; Sherlock, Wallace

    2013-01-01

    In order to be successful, students must acquire the language of science for both oral and written communication. In this article we examine an oral language learning technique called choral repetition for its role in building literacy in the context of an animal physiology course. For 3 weeks, the instructor conducted choral repetitions of nine…

  16. The use of digit and sentence repetition in the identification of ...

    African Journals Online (AJOL)

    Kate H

    be more sensitive than others for the difference between the performance of the ... assessment instruments, screening tools that employ repetition tasks can be ... Whilst “specific language impairment” is widely used in academic or ... Digit repetition requires a person to repeat in the correct order a series of digits presented.

  17. Repetitive sequences in plant nuclear DNA: types, distribution, evolution and function.

    Science.gov (United States)

    Mehrotra, Shweta; Goyal, Vinod

    2014-08-01

    Repetitive DNA sequences are a major component of eukaryotic genomes and may account for up to 90% of the genome size. They can be divided into minisatellite, microsatellite and satellite sequences. Satellite DNA sequences are considered to be a fast-evolving component of eukaryotic genomes, comprising tandemly-arrayed, highly-repetitive and highly-conserved monomer sequences. The monomer unit of satellite DNA is 150-400 base pairs (bp) in length. Repetitive sequences may be species- or genus-specific, and may be centromeric or subtelomeric in nature. They exhibit cohesive and concerted evolution caused by molecular drive, leading to high sequence homogeneity. Repetitive sequences accumulate variations in sequence and copy number during evolution, hence they are important tools for taxonomic and phylogenetic studies, and are known as "tuning knobs" in the evolution. Therefore, knowledge of repetitive sequences assists our understanding of the organization, evolution and behavior of eukaryotic genomes. Repetitive sequences have cytoplasmic, cellular and developmental effects and play a role in chromosomal recombination. In the post-genomics era, with the introduction of next-generation sequencing technology, it is possible to evaluate complex genomes for analyzing repetitive sequences and deciphering the yet unknown functional potential of repetitive sequences. Copyright © 2014 The Authors. Production and hosting by Elsevier Ltd.. All rights reserved.

  18. High-repetition-rate XeCl waveguide laser without gas flow

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, C.P.; Gordon C. III; Moutoulas, C.; Feldman, B.J.

    1987-03-01

    Operation of a microwave discharge XeCl laser at pulse-repetition rates extending to 8 kHz without flow of the laser gas is reported. Present limits on pulse-repetition rate appear to be imposed by thermally induced refractive-index gradients.

  19. The Relationship between Anxiety and Repetitive Behaviours in Autism Spectrum Disorder

    Science.gov (United States)

    Rodgers, J.; Glod, M.; Connolly, B.; McConachie, H.

    2012-01-01

    Children with Autism Spectrum Disorder are vulnerable to anxiety. Repetitive behaviours are a core feature of Autism Spectrum Disorder (ASD) and have been associated with anxiety. This study examined repetitive behaviours and anxiety in two groups of children with autism spectrum disorder, those with high anxiety and those with lower levels of…

  20. Randomization of Symbol Repetition of Punch Cards with Superimposed Coding in Information-Search Systems.

    Science.gov (United States)

    Pirovich, L. Ya

    The article shows the effect of the irregularity of using separate symbols on search noise on punch cards with superimposed symbol coding in information-search system (IPS). A binomial law of random value distribution of repetition of each symbol is established and analyzed. A method of determining the maximum value of symbol repetition is…

  1. SD-REE: A Cryptographic Method to Exclude Repetition from a Message

    CERN Document Server

    Dey, Somdip

    2012-01-01

    In this paper, the author presents a new cryptographic technique, SD-REE, to exclude the repetitive terms in a message, when it is to be encrypted, so that it becomes almost impossible for a person to retrieve or predict the original message from the encrypted message. In modern world, cryptography hackers try to break a code or cryptographic algorithm [1,2] or retrieve the key, used for encryption, by inserting repetitive bytes / characters in the message and encrypt the message or by analyzing repetitions in the encrypted message, to find out the encryption algorithm or retrieve the key used for the encryption. But in SD-REE method the repetitive bytes / characters are removed and there is no trace of any repetition in the message, which was encrypted.

  2. Feasibility of High-Repetition, Task-Specific Training for Individuals With Upper-Extremity Paresis

    Science.gov (United States)

    Waddell, Kimberly J.; Birkenmeier, Rebecca L.; Moore, Jennifer L.; Hornby, T. George

    2014-01-01

    OBJECTIVE. We investigated the feasibility of delivering an individualized, progressive, high-repetition upper-extremity (UE) task-specific training protocol for people with stroke in the inpatient rehabilitation setting. METHOD. Fifteen patients with UE paresis participated in this study. Task-specific UE training was scheduled for 60 min/day, 4 days/wk, during occupational therapy for the duration of a participant’s inpatient stay. During each session, participants were challenged to complete ≥300 repetitions of various tasks. RESULTS. Participants averaged 289 repetitions/session, spending 47 of 60 min in active training. Participants improved on impairment and activity level outcome measures. CONCLUSION. People with stroke in an inpatient setting can achieve hundreds of repetitions of task-specific training in 1-hr sessions. As expected, all participants improved on functional outcome measures. Future studies are needed to determine whether this high-repetition training program results in better outcomes than current UE interventions. PMID:25005508

  3. Repetitive DNA in three Gramineae species with low DNA content.

    Science.gov (United States)

    Deshpande, V G; Ranjekar, P K

    1980-08-01

    The genomes of three Gramineae species, namely finger millet (Eleusine coracana), pearl millet (Pennisetum americanum) and rice (Oryza sativa) are characterized by studying their DNA denaturation-reassociation properties. The reassociation kinetics measurement of the sonicated DNA (500--700 nucleotide pairs) indicate the presence of a heterogeneous, repetitive DNA fraction accounting for 49--54% of the total DNA in all three species. From the cot 1/2 value of the slow reassociating DNA, the genome size is estimated as 3.0 X 10(8) np in finger millet, 7.8 X 10(8) np in pearl millet and 9.0 X 10(8) np in rice. The melting patterns of the total DNAs reveal Tm value of 88.6 degrees C in the case of pearl millet and 85.0 degrees C in the case of finger millet and rice. Total repetitive and cot 1.0 DNA fractions in all the three species are isolated and their melting properties are compared with those of respective sonicated DNAs. In finger millet, the Tm values of cot 25 and cot 1 fractions are lower by 10.8 degrees C and 12.8 degrees C, respectively, than that of sonicated DNA and thus exhibit the presence of a base pair mismatch in the range of 10.8--12.8%. In rice, the Tm values of the fractions cot 50 and cot 1 are slightly lower than that of sonicated DNA and reveal a nucleotide mismatching of only 1.8--3.8%. In the case of pearl millet cot 10 DNA fraction a high-melting DNA component (Tm = 92 degrees C) representing 12% of the total cot 10 DNA and a low-melting component with a Tm of 78 degrees C are present. In cot 1 DNA fraction of pearl millet the proportion of the high-melting component is 35% and it has a Tm or 94.8 degrees C. Optical reassociation studies of cot 1.0 DNA fractions have revealed the presence of two kinetically distinct components, namely minor fast-reassociating and major slow-reassociating, having complexities in the range of 330--390 np and 1.28 X 10(5)--6.0 X 10(5) np, respectively in pearl millet and rice and only one DNA fraction with an

  4. Serial rapists and their victims: reenactment and repetition.

    Science.gov (United States)

    Burgess, A W; Hazelwood, R R; Rokous, F E; Hartman, C R; Burgess, A G

    1988-01-01

    The major finding in this study of 41 serial rapists is the large numbers of reported and unreported victims. For over 1200 attempted and completed rapes, there were 200 convictions. The hidden rapes or earliest nonreported victims of these men as boys and adolescents were identified from their families, their neighborhood, and their schools. Examining the possible link between childhood sexual abuse and criminal behavior in this sample of 41 serial rapists, 56.1% were judged to have at least one forced or exploitive abuse experience in boyhood, as compared to a study of 2,972 college males reporting 7.3% experiencing boyhood sexual abuse. Looking within the abused samples, 56.1% of the rapists reported forced sex, compared to the college sample's 30.4%. Also, the rapist sample revealed higher rates of family member as abuser (48.4%), compared to 22.2% for the college sample. Retrospective reconstruction of the sexual activities and assertive behaviors of these men as boys reveals that 51% of the boys reenact the abuse as a preadolescent with their earliest victims being known to them (48% as neighborhood girls), family (25% as sisters), or girlfriend (25%). The onset of rape fantasies in midadolescence (mean age 16.9) crystalizes the earlier sexually initiated behaviors into juvenile behaviors of spying, fetish burglaries, molestations, and rapes. Repetition of these juvenile behaviors set their criminal patters on strangers--their next group of victims. To reduce victimization, serial rapists need to be identified early and stopped. This means acknowledging and reporting boy sexual abuse. This includes being sensitive to the reenactment behaviors noted in the initiated activities of abused children, which in turn need to be differentiated from peer play. Closer attention needs to be paid to families with incest behavior to insure that younger children are protected. Adolescents showing early repetitive juvenile delinquent behaviors must be assessed for physical

  5. The HSP expression of passive repetitive plyometric trained skeletal muscle.

    Science.gov (United States)

    Hsu, Cheng-Chen; Hsu, Mei-Chich; Huang, Mao-Shung; Chen, Chuan-Show; Shiang, Tzyy-Yuang; Wang, Chiou-Huey; Chen, Tzuping; Su, Borcherng

    2005-01-01

    This study aims to understand the effect of ten-week passive repetitive plyometric (PRP) training on human skeletal muscle and the application of PRP training for performance. Vastus lateralis of nine candidates were aspirated before (pre) and after (post) PRP training. Histochemical approaches with regular hematoxylene-eosin (HE) and Mallory's phosphotungstic acid hematoxylin (PTAH) stains were used to demonstrate the changes of muscle fibers. Immunohistochemical studies with heat shock protein (anti-hsp72, Stressgen, Canada) were employed to display cellular activities. Each set of slides was quantitatively analyzed by using a modified morphometric method (Russ and Dehoff, 1999) on a Nikon ECLIPSE 80i microscope, equipped with an Evolution VF COOLED color video camera, and the Image-Pro Plus software (5.0 for Win; Media Cybernetics, USA). Finally, hsp72 mRNAs of both pre-PRP and post-PRP specimens were amplified through RT-PCR. Signal intensities were read by a densitometer and analyzed through the SPSS (11.0 for Win) statistically. Post-PRP muscle cells demonstrated hypertrophic change with increased cellular content and a narrowed inter-cellular space according to both HE and PTAH profiles. Post-PRP cellular hsp72 proteins were higher by up to five percent, as measured by a gray-scale reading. Further, after a training period of 10 weeks, hsp72 mRNA expression was several times higher.

  6. Developments of repetitive pneumatic pipe-gun pellet injector

    Energy Technology Data Exchange (ETDEWEB)

    Sudo, Shigeru [National Inst. for Fusion Science, Nagoya (Japan); Viniar, I.

    1997-05-01

    A pellet injector of repetitive pneumatic pipe-gun type has been designed for advanced plasma fueling applications. This new concept is estimated to be able to reduce the time for pellet formation by an in situ technique from 3 - 5 minutes to 2 - 10 seconds. The basic idea of the new approach to pellet formation is to supply a hydrogen isotope pellet through a copper porous unit into a pipe-gun-type barrel. Two modes are possible: (1) to push liquid hydrogen isotope through a porous unit and re-freezing inside of the barrel, (2) to push solid hydrogen isotope through a porous unit to the inside of the barrel. This principle provides a continuous injection of an unlimited amount of pellets. For demonstration of the proof-of-principle, several experiments have been carried out. Hydrogen pellets of 3 mm in diameter and 3 to 10 mm in length were accelerated to 1.2 km/s at a rate of 1 pellet per 10 - 34 s with a manually controlled injector operation. (author)

  7. Electromyographical Study on Muscle Fatigue in Repetitive Forearm Tasks

    Institute of Scientific and Technical Information of China (English)

    DAI Wentao; ZHAO Xiaorong; WANG Zhenglun; YANG Lei

    2007-01-01

    The purpose of this study was to examine whether repetitive muscle tasks in low weight load might influence the fatigue of forearm muscles, and to identify ergonomic risk factors of forearm muscle fatigue in these tasks. Sixteen healthy male volunteers performed eight wrist extensions in different frequency, weight and angle loads while being instructed to keep a dominant upper limb posture as constant as possible. Surface electromyograph (sEMG) was recorded from right extensors digitorium (ED), flexor carpi radialis (FCR), flexor carpi ulnaris (FCU) and extensor carpi ulnaris (ECU) during the task performance. Our results showed that mean power frequency (MPF) and median frequency (MF) values of ED, FCR and FCU were significantly lower (P<0.05) at high frequency load level than at low load level. However, MPF and MF values of ED were significantly lower (P<0.01) in higher load groups of frequency, angle and weight than in lower load groups. These results indicated that the fatigue of muscles varied in the same task, and the number-one risk factor of ECU, ED and FCR was angle load.

  8. The interaction between duration, velocity and repetitive auditory stimulation.

    Science.gov (United States)

    Makin, Alexis D J; Poliakoff, Ellen; Dillon, Joe; Perrin, Aimee; Mullet, Thomas; Jones, Luke A

    2012-03-01

    Repetitive auditory stimulation (with click trains) and visual velocity signals both have intriguing effects on the subjective passage of time. Previous studies have established that prior presentation of auditory clicks increases the subjective duration of subsequent sensory input, and that faster moving stimuli are also judged to have been presented for longer (the time dilation effect). However, the effect of clicks on velocity estimation is unknown, and the nature of the time dilation effect remains ambiguous. Here were present a series of five experiments to explore these phenomena in more detail. Participants viewed a rightward moving grating which traveled at velocities ranging from 5 to 15°/s and which lasted for durations of 500 to 1500 ms. Gratings were preceded by clicks, silence or white noise. It was found that both clicks and higher velocities increased subjective duration. It was also found that the time dilation effect was a constant proportion of stimulus duration. This implies that faster velocity increases the rate of the pacemaker component of the internal clock. Conversely, clicks increased subjective velocity, but the magnitude of this effect was not proportional to actual velocity. Through considerations of these results, we conclude that clicks independently affect velocity and duration representations.

  9. Improved discrimination of visual stimuli following repetitive transcranial magnetic stimulation.

    Directory of Open Access Journals (Sweden)

    Michael L Waterston

    Full Text Available BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS at certain frequencies increases thresholds for motor-evoked potentials and phosphenes following stimulation of cortex. Consequently rTMS is often assumed to introduce a "virtual lesion" in stimulated brain regions, with correspondingly diminished behavioral performance. METHODOLOGY/PRINCIPAL FINDINGS: Here we investigated the effects of rTMS to visual cortex on subjects' ability to perform visual psychophysical tasks. Contrary to expectations of a visual deficit, we find that rTMS often improves the discrimination of visual features. For coarse orientation tasks, discrimination of a static stimulus improved consistently following theta-burst stimulation of the occipital lobe. Using a reaction-time task, we found that these improvements occurred throughout the visual field and lasted beyond one hour post-rTMS. Low-frequency (1 Hz stimulation yielded similar improvements. In contrast, we did not find consistent effects of rTMS on performance in a fine orientation discrimination task. CONCLUSIONS/SIGNIFICANCE: Overall our results suggest that rTMS generally improves or has no effect on visual acuity, with the nature of the effect depending on the type of stimulation and the task. We interpret our results in the context of an ideal-observer model of visual perception.

  10. Power neodymium-glass amplifier of a repetitively pulsed laser

    Energy Technology Data Exchange (ETDEWEB)

    Vinogradov, Aleksandr V; Gaganov, V E; Garanin, Sergey G; Zhidkov, N V; Krotov, V A; Martynenko, S P; Pozdnyakov, E V; Solomatin, I I [Russian Federal Nuclear Center ' All-Russian Research Institute of Experimental Physics' , Sarov, Nizhnii Novgorod region (Russian Federation)

    2011-11-30

    A neodymium-glass diode-pumped amplifier with a zigzag laser beam propagation through the active medium was elaborated; the amplifier is intended for operation in a repetitively pulsed laser. An amplifier unit with an aperture of 20 Multiplication-Sign 25 mm and a {approx}40-cm long active medium was put to a test. The energy of pump radiation amounts to 140 J at a wavelength of 806 nm for a pump duration of 550 {mu}s. The energy parameters of the amplifier were experimentally determined: the small-signal gain per pass {approx}3.2, the linear gain {approx}0.031 cm{sup -1} with a nonuniformity of its distribution over the aperture within 15%, the stored energy of 0.16 - 0.21 J cm{sup -3}. The wavefront distortions in the zigzag laser-beam propagation through the active element of the amplifier did not exceed 0.4{lambda} ({lambda} = 0.63 {mu}m is the probing radiation wavelength).

  11. Use of repetitive transcranial magnetic stimulation for treatment in psychiatry.

    Science.gov (United States)

    Aleman, André

    2013-08-01

    The potential of noninvasive neurostimulation by repetitive transcranial magnetic stimulation (rTMS) for improving psychiatric disorders has been studied increasingly over the past two decades. This is especially the case for major depression and for auditory-verbal hallucinations in schizophrenia. The present review briefly describes the background of this novel treatment modality and summarizes evidence from clinical trials into the efficacy of rTMS for depression and hallucinations. Evidence for efficacy in depression is stronger than for hallucinations, although a number of studies have reported clinically relevant improvements for hallucinations too. Different stimulation parameters (frequency, duration, location of stimulation) are discussed. There is a paucity of research into other psychiatric disorders, but initial evidence suggests that rTMS may also hold promise for the treatment of negative symptoms in schizophrenia, obsessive compulsive disorder and post-traumatic stress disorder. It can be concluded that rTMS induces alterations in neural networks relevant for psychiatric disorders and that more research is needed to elucidate efficacy and underlying mechanisms of action.

  12. Embryotoxicity following repetitive maternal exposure to scorpion venom

    Directory of Open Access Journals (Sweden)

    BN Hmed

    2012-01-01

    Full Text Available Although it is a frequent accident in a few countries, scorpion envenomation during pregnancy remains scarcely studied. In the present study, the effects of repetitive maternal exposure to Buthus occitanus tunetanus venom are investigated and its possible embryotoxic consequences on rats. Primigravid rats received a daily intraperitoneal dose of 1 mL/kg of saline solution or 300 µg/kg of crude scorpion venom, from the 7th to the 13th day of gestation. On the 21st day, the animals were deeply anesthetized using diethyl-ether. Then, blood was collected for chemical parameter analysis. Following euthanasia, morphometric measurements were carried out. The results showed a significant increase in maternal heart and lung absolute weights following venom treatment. However, the mean placental weight per rat was significantly diminished. Furthermore, blood urea concentration was higher in exposed rats (6.97 ± 0.62 mmol/L than in those receiving saline solution (4.94 ± 0.90 mmol/L. Many organs of venom-treated rat fetuses (brain, liver, kidney and spleen were smaller than those of controls. On the contrary, fetal lungs were significantly heavier in fetuses exposed to venom (3.2 ± 0.4 g than in the others (3.0 ± 0.2 g. Subcutaneous blood clots, microphthalmia and total body and tail shortening were also observed in venom-treated fetuses. It is concluded that scorpion envenomation during pregnancy potentially causes intrauterine fetal alterations and growth impairment.

  13. [Repetitive transcranial magnetic stimulation: A potential therapy for cognitive disorders?

    Science.gov (United States)

    Nouhaud, C; Sherrard, R M; Belmin, J

    2017-03-01

    Considering the limited effectiveness of drugs treatments in cognitive disorders, the emergence of noninvasive techniques to modify brain function is very interesting. Among these techniques, repetitive transcranial magnetic stimulation (rTMS) can modulate cortical excitability and have potential therapeutic effects on cognition and behaviour. These effects are due to physiological modifications in the stimulated cortical tissue and their associated circuits, which depend on the parameters of stimulation. The objective of this article is to specify current knowledge and efficacy of rTMS in cognitive disorders. Previous studies found very encouraging results with significant improvement of higher brain functions. Nevertheless, these few studies have limits: a few patients were enrolled, the lack of control of the mechanisms of action by brain imaging, insufficiently formalized technique and variability of cognitive tests. It is therefore necessary to perform more studies, which identify statistical significant improvement and to specify underlying mechanisms of action and the parameters of use of the rTMS to offer rTMS as a routine therapy for cognitive dysfunction.

  14. Repetitive transcranial magnetic stimulator with controllable pulse parameters

    Science.gov (United States)

    Peterchev, Angel V.; Murphy, David L.; Lisanby, Sarah H.

    2011-06-01

    The characteristics of transcranial magnetic stimulation (TMS) pulses influence the physiological effect of TMS. However, available TMS devices allow very limited adjustment of the pulse parameters. We describe a novel TMS device that uses a circuit topology incorporating two energy storage capacitors and two insulated-gate bipolar transistor (IGBT) modules to generate near-rectangular electric field pulses with adjustable number, polarity, duration, and amplitude of the pulse phases. This controllable pulse parameter TMS (cTMS) device can induce electric field pulses with phase widths of 10-310 µs and positive/negative phase amplitude ratio of 1-56. Compared to conventional monophasic and biphasic TMS, cTMS reduces energy dissipation up to 82% and 57% and decreases coil heating up to 33% and 41%, respectively. We demonstrate repetitive TMS trains of 3000 pulses at frequencies up to 50 Hz with electric field pulse amplitude and width variability less than the measurement resolution (1.7% and 1%, respectively). Offering flexible pulse parameter adjustment and reduced power consumption and coil heating, cTMS enhances existing TMS paradigms, enables novel research applications and could lead to clinical applications with potentially enhanced potency.

  15. Unraveling the cellular and molecular mechanisms of repetitive magnetic stimulation

    Directory of Open Access Journals (Sweden)

    Florian eMüller-Dahlhaus

    2013-12-01

    Full Text Available Despite numerous clinical studies, which have investigated the therapeutic potential of repetitive transcranial magnetic stimulation (rTMS in various brain diseases, our knowledge of the cellular and molecular mechanisms underlying rTMS-based therapies remains limited. Thus, a deeper understanding of rTMS-induced neural plasticity is required to optimize current treatment protocols. Studies in small animals or appropriate in vitro preparations (including models of brain diseases provide highly useful experimental approaches in this context. State-of-the-art electrophysiological and live-cell imaging techniques that are well established in basic neuroscience can help answering some of the major questions in the field, such as (i which neural structures are activated during TMS, (ii how does rTMS induce Hebbian plasticity, and (iii are other forms of plasticity (e.g., metaplasticity, structural plasticity induced by rTMS? We argue that data gained from these studies will support the development of more effective and specific applications of rTMS in clinical practice.

  16. Combinatorics on words Christoffel words and repetitions in words

    CERN Document Server

    Berstel, Jean; Reutenauer, Christophe; Saliola, Franco V

    2008-01-01

    The two parts of this text are based on two series of lectures delivered by Jean Berstel and Christophe Reutenauer in March 2007 at the Centre de Recherches Mathématiques, Montréal, Canada. Part I represents the first modern and comprehensive exposition of the theory of Christoffel words. Part II presents numerous combinatorial and algorithmic aspects of repetition-free words stemming from the work of Axel Thue-a pioneer in the theory of combinatorics on words. A beginner to the theory of combinatorics on words will be motivated by the numerous examples, and the large variety of exercises, which make the book unique at this level of exposition. The clean and streamlined exposition and the extensive bibliography will also be appreciated. After reading this book, beginners should be ready to read modern research papers in this rapidly growing field and contribute their own research to its development. Experienced readers will be interested in the finitary approach to Sturmian words that Christoffel words offe...

  17. Characterizing Aciniform Silk Repetitive Domain Backbone Dynamics and Hydrodynamic Modularity

    Directory of Open Access Journals (Sweden)

    Marie-Laurence Tremblay

    2016-08-01

    Full Text Available Spider aciniform (wrapping silk is a remarkable fibrillar biomaterial with outstanding mechanical properties. It is a modular protein consisting, in Argiope trifasciata, of a core repetitive domain of 200 amino acid units (W units. In solution, the W units comprise a globular folded core, with five α-helices, and disordered tails that are linked to form a ~63-residue intrinsically disordered linker in concatemers. Herein, we present nuclear magnetic resonance (NMR spectroscopy-based 15N spin relaxation analysis, allowing characterization of backbone dynamics as a function of residue on the ps–ns timescale in the context of the single W unit (W1 and the two unit concatemer (W2. Unambiguous mapping of backbone dynamics throughout W2 was made possible by segmental NMR active isotope-enrichment through split intein-mediated trans-splicing. Spectral density mapping for W1 and W2 reveals a striking disparity in dynamics between the folded core and the disordered linker and tail regions. These data are also consistent with rotational diffusion behaviour where each globular domain tumbles almost independently of its neighbour. At a localized level, helix 5 exhibits elevated high frequency dynamics relative to the proximal helix 4, supporting a model of fibrillogenesis where this helix unfolds as part of the transition to a mixed α-helix/β-sheet fibre.

  18. Designing a Repetitive Group Sampling Plan for Weibull Distributed Processes

    Directory of Open Access Journals (Sweden)

    Aijun Yan

    2016-01-01

    Full Text Available Acceptance sampling plans are useful tools to determine whether the submitted lots should be accepted or rejected. An efficient and economic sampling plan is very desirable for the high quality levels required by the production processes. The process capability index CL is an important quality parameter to measure the product quality. Utilizing the relationship between the CL index and the nonconforming rate, a repetitive group sampling (RGS plan based on CL index is developed in this paper when the quality characteristic follows the Weibull distribution. The optimal plan parameters of the proposed RGS plan are determined by satisfying the commonly used producer’s risk and consumer’s risk at the same time by minimizing the average sample number (ASN and then tabulated for different combinations of acceptance quality level (AQL and limiting quality level (LQL. The results show that the proposed plan has better performance than the single sampling plan in terms of ASN. Finally, the proposed RGS plan is illustrated with an industrial example.

  19. Code domains in tandem repetitive DNA sequence structures.

    Science.gov (United States)

    Vogt, P

    1992-10-01

    Traditionally, many people doing research in molecular biology attribute coding properties to a given DNA sequence if this sequence contains an open reading frame for translation into a sequence of amino acids. This protein coding capability of DNA was detected about 30 years ago. The underlying genetic code is highly conserved and present in every biological species studied so far. Today, it is obvious that DNA has a much larger coding potential for other important tasks. Apart from coding for specific RNA molecules such as rRNA, snRNA and tRNA molecules, specific structural and sequence patterns of the DNA chain itself express distinct codes for the regulation and expression of its genetic activity. A chromatin code has been defined for phasing of the histone-octamer protein complex in the nucleosome. A translation frame code has been shown to exist that determines correct triplet counting at the ribosome during protein synthesis. A loop code seems to organize the single stranded interaction of the nascent RNA chain with proteins during the splicing process, and a splicing code phases successive 5' and 3' splicing sites. Most of these DNA codes are not exclusively based on the primary DNA sequence itself, but also seem to include specific features of the corresponding higher order structures. Based on the view that these various DNA codes are genetically instructive for specific molecular interactions or processes, important in the nucleus during interphase and during cell division, the coding capability of tandem repetitive DNA sequences has recently been reconsidered.

  20. Variation and repetition in the spelling of young children.

    Science.gov (United States)

    Treiman, Rebecca; Decker, Kristina; Kessler, Brett; Pollo, Tatiana Cury

    2015-04-01

    A number of investigators have suggested that young children, even those who do not yet represent the phonological forms of words in their spellings, tend to use different strings of letters for different words. However, empirical evidence that children possess a concept of between-word variation has been weak. In a study by Pollo, Kessler, and Treiman (2009), in fact, prephonological spellers were more likely to write different words in the same way than would be expected on the basis of chance, not less likely. In the current study, preschool-age prephonological and phonological spellers showed a tendency to repeat spellings and parts of spellings that they had recently used. However, even prephonological spellers (mean age∼4 years 8 months) showed more repetition when spelling the same word twice in succession than when spelling different words. The results suggest that children who have not yet learned to use writing to represent the sounds of speech show some knowledge that writing represents words and, thus, should vary to show differences between them. The results further suggest that in spelling, as in other domains, children have a tendency to repeat recent behaviors. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Characterization and distribution of repetitive elements in association with genes in the human genome.

    Science.gov (United States)

    Liang, Kai-Chiang; Tseng, Joseph T; Tsai, Shaw-Jenq; Sun, H Sunny

    2015-08-01

    Repetitive elements constitute more than 50% of the human genome. Recent studies implied that the complexity of living organisms is not just a direct outcome of a number of coding sequences; the repetitive elements, which do not encode proteins, may also play a significant role. Though scattered studies showed that repetitive elements in the regulatory regions of a gene control gene expression, no systematic survey has been done to report the characterization and distribution of various types of these repetitive elements in the human genome. Sequences from 5' and 3' untranslated regions and upstream and downstream of a gene were downloaded from the Ensembl database. The repetitive elements in the neighboring of each gene were identified and classified using cross-matching implemented in the RepeatMasker. The annotation and distribution of distinct classes of repetitive elements associated with individual gene were collected to characterize genes in association with different types of repetitive elements using systems biology program. We identified a total of 1,068,400 repetitive elements which belong to 37-class families and 1235 subclasses that are associated with 33,761 genes and 57,365 transcripts. In addition, we found that the tandem repeats preferentially locate proximal to the transcription start site (TSS) of genes and the major function of these genes are involved in developmental processes. On the other hand, interspersed repetitive elements showed a tendency to be accumulated at distal region from the TSS and the function of interspersed repeat-containing genes took part in the catabolic/metabolic processes. Results from the distribution analysis were collected and used to construct a gene-based repetitive element database (GBRED; http://www.binfo.ncku.edu.tw/GBRED/index.html). A user-friendly web interface was designed to provide the information of repetitive elements associated with any particular gene(s). This is the first study focusing on the gene

  2. Fuzzy Adaptive Repetitive Control for Periodic Disturbance with Its Application to High Performance Permanent Magnet Synchronous Motor Speed Servo Systems

    National Research Council Canada - National Science Library

    Junxiao Wang

    2016-01-01

    .... Then, the mathematical model of PMSM is given. Subsequently, a fuzzy adaptive repetitive controller based on repetitive control and fuzzy logic control is designed for the PMSM speed servo system...

  3. Safety and efficacy of low fluence, high repetition rate versus high fluence, low repetition rate 810-nm diode laser for axillary hair removal in Chinese women.

    Science.gov (United States)

    Li, Wenhai; Liu, Chengyi; Chen, Zhou; Cai, Lin; Zhou, Cheng; Xu, Qianxi; Li, Houmin; Zhang, Jianzhong

    2016-11-01

    High-fluence diode lasers with contact cooling have emerged as the gold standard to remove unwanted hair. Lowering the energy should result in less pain and could theoretically affect the efficacy of the therapy. To compare the safety and efficacy of a low fluence high repetition rate 810-nm diode laser to those of a high fluence, low repetition rate diode laser for permanent axillary hair removal in Chinese women. Ninety-two Chinese women received four axillae laser hair removal treatments at 4-week intervals using the low fluence, high repetition rate 810-nm diode laser in super hair removal (SHR) mode on one side and the high fluence, low repetition rate diode laser in hair removal (HR) mode on the other side. Hair counts were done at each follow-up visit and 6-month follow-up after the final laser treatment using a "Hi Quality Hair Analysis Program System"; the immediate pain score after each treatment session was recorded by a visual analog scale. The overall median reduction of hair was 90.2% with the 810-nm diode laser in SHR mode and 87% with the same laser in HR mode at 6-month follow-up. The median pain scores in SHR mode and in HR mode were 2.75 and 6.75, respectively. Low fluence, high repetition rate diode laser can efficiently remove unwanted hair but also significantly improve tolerability and reduce adverse events during the course of treatment.

  4. Sentence repetition is a measure of children's language skills rather than working memory limitations.

    Science.gov (United States)

    Klem, Marianne; Melby-Lervåg, Monica; Hagtvet, Bente; Lyster, Solveig-Alma Halaas; Gustafsson, Jan-Eric; Hulme, Charles

    2015-01-01

    Sentence repetition tasks are widely used in the diagnosis and assessment of children with language difficulties. This paper seeks to clarify the nature of sentence repetition tasks and their relationship to other language skills. We present the results from a 2-year longitudinal study of 216 children. Children were assessed on measures of sentence repetition, vocabulary knowledge and grammatical skills three times at approximately yearly intervals starting at age 4. Sentence repetition was not a unique longitudinal predictor of the growth of language skills. A unidimensional language latent factor (defined by sentence repetition, vocabulary knowledge and grammatical skills) provided an excellent fit to the data, and language abilities showed a high degree of longitudinal stability. Sentence repetition is best seen as a reflection of an underlying language ability factor rather than as a measure of a separate construct with a specific role in language processing. Sentence repetition appears to be a valuable tool for language assessment because it draws upon a wide range of language processing skills. © 2014 The Authors. Developmental Science Published by John Wiley & Sons Ltd.

  5. Repetitive sequences in Eurasian lynx (Lynx lynx L.) mitochondrial DNA control region.

    Science.gov (United States)

    Sindičić, Magda; Gomerčić, Tomislav; Galov, Ana; Polanc, Primož; Huber, Duro; Slavica, Alen

    2012-06-01

    Mitochondrial DNA (mtDNA) control region (CR) of numerous species is known to include up to five different repetitive sequences (RS1-RS5) that are found at various locations, involving motifs of different length and extensive length heteroplasmy. Two repetitive sequences (RS2 and RS3) on opposite sides of mtDNA central conserved region have been described in domestic cat (Felis catus) and some other felid species. However, the presence of repetitive sequence RS3 has not been detected in Eurasian lynx (Lynx lynx) yet. We analyzed mtDNA CR of 35 Eurasian lynx (L. lynx L.) samples to characterize repetitive sequences and to compare them with those found in other felid species. We confirmed the presence of 80 base pairs (bp) repetitive sequence (RS2) at the 5' end of the Eurasian lynx mtDNA CR L strand and for the first time we described RS3 repetitive sequence at its 3' end, consisting of an array of tandem repeats five to ten bp long. We found that felid species share similar RS3 repetitive pattern and fundamental repeat motif TACAC.

  6. Environmental conditions associated with repetitive behavior in a group of African elephants.

    Science.gov (United States)

    Hasenjager, Matthew J; Bergl, Richard A

    2015-01-01

    Repetitive movement patterns are commonly observed in zoo elephants. The extent to which these behaviors constitute a welfare concern varies, as their expression ranges from stereotypies to potentially beneficial anticipatory behaviors. Nevertheless, their occurrence in zoo animals is often viewed negatively. To better identify conditions that prompt their performance, observations were conducted on six African elephants (Loxodonta africana) at the North Carolina Zoo. Individuals spent most of their time engaged in feeding, locomotion, resting, and repetitive behavior. Both generalized estimating equation and zero-inflated negative binomial models were used to identify factors associated with increased rates of repetitive behavior. Time of day in conjunction with location on- or off-exhibit best explained patterns of repetitive behavior. Repetitive behaviors occurred at a lower rate in the morning when on-exhibit, as compared to afternoons on-exhibit or at any time of day off-exhibit. Increased repetitive behavior rates observed on-exhibit in the afternoon prior to the evening transfer and feeding were possibly anticipatory responses towards those events. In contrast, consistently elevated frequencies of repetitive behavior off-exhibit at all times of day could be related to differences in exhibit complexity between off-exhibit and on-exhibit areas, as well as a lack of additional foraging opportunities. Our study contributes valuable information on captive elephant behavior and represents a good example of how behavioral research can be employed to improve management of zoo animals.

  7. A longitudinal investigation of perfectionism and repetitive negative thinking in perinatal depression.

    Science.gov (United States)

    Egan, Sarah J; Kane, Robert T; Winton, Karen; Eliot, Catherine; McEvoy, Peter M

    2017-10-01

    Repetitive negative thinking and perfectionism have both been proposed as processes that are related to depressive symptoms. The purpose of this study was to investigate concurrent and prospective relationships between antenatal and postnatal depression, perfectionism, and repetitive negative thinking. A longitudinal design was used and 71 women were followed from their third trimester of pregnancy to six weeks post birth. A structural equation model was tested with antenatal perfectionism predicting antenatal repetitive negative thinking, perfectionism predicting postnatal depression, and antenatal repetitive negative thinking predicting antenatal and postnatal depression. The final model provided an adequate fit to the data but the pathway from antenatal repetitive negative thinking to postnatal depression was not significant. The findings provide support for the role of perfectionism and repetitive negative thinking in the onset and maintenance of perinatal symptoms of depression. It is suggested that future research investigates the efficacy of targeting repetitive negative thinking and perfectionism in pregnancy to examine if this can reduce perinatal depression. Copyright © 2017. Published by Elsevier Ltd.

  8. Physiological responses to four hours of low-level repetitive work.

    Science.gov (United States)

    Garde, A Helene; Hansen, Ase M; Jensen, Bente R

    2003-12-01

    The study investigated physiological responses to 4 hours of standardized low-level repetitive work. It was hypothesized that accumulative effects not observed after 1 hour could be found after 4 hours of repetitive work. Ten healthy women performed intermittent (5 seconds + 5 seconds) handgrip contractions at 10% of the maximal voluntary contraction combined with mental demands for concentration and attention. Muscle activity in the working forearm muscles, cardiovascular responses, and concentrations of biomarkers in biological fluids were recorded along with exerted force, performance, and ratings of perceived physical exertion (RPE), and perceived mental exertion. The urinary epinephrine, norepinephrine, and cortisol concentrations were higher during the repetitive task than on a reference day, but only the norepinephrine concentrations increased progressively during the 4 hours. In accordance, the RPE recorded for the hand, forearm, and shoulder regions increased progressively. For the remaining physiological measures, no accumulative changes were found. Forearm muscle activity was higher during a mental reference task with lower exerted force than during the repetitive task. The variation in exerted force was higher during the repetitive task than during a force reference task without mental demands. The urinary biomarkers were increased during the repetitive task. However, only norepinephrine increased progressively during the 4 hours. Forearm muscle activity during a mental reference task with low exerted force indicated attention-related muscle activity. Finally, it was indicated that repetitive work including high demands for attention is performed at the expense of the precision of the exerted force.

  9. Stigmatization of repetitive hand use in newspaper reports of hand illness.

    Science.gov (United States)

    Anthony, Shawn; Lozano-Calderon, Santiago; Ring, David

    2008-03-01

    Failure to provide a balanced evidence-based consideration of the role of activity in illness can stigmatize individuals and their activities. We assessed the prevalence of language that stigmatized repetitive hand use and those that use their hand repetitively in newspaper coverage of common hand illnesses. The LexisNexis Academic database was used to search five major US newspapers for articles containing keywords about common hand illnesses during a 3-year period. Article language was assessed for stigmatization of activities involving repetitive hand use as well as for stigmatization of patients who use their hand repetitively. One hundred and twenty-four articles on hand illnesses were identified. Of these, 65.3% of articles stigmatized activities involving repetitive hand use, including 96.6% of articles discussing overuse injury of the hand, 90% of articles discussing tendonitis or tenosynovitis, and 51.8% of articles discussing carpal tunnel syndrome. Patient stigmatization was documented in 30.6% of the newspaper articles. Stigmatizing statements were most commonly made by journalists (94.8%), followed by patients (3.1%), and physicians (2.1%). Language that stigmatizes repetitive hand use and patients who use their hand repetitively is prevalent among US newspaper articles. Both health professionals and journalists reporting health-related news should be more sensitive to the use of stigmatizing language and provide a more balanced, measured, and evidenced-based account of hand illnesses.

  10. Repetitive behavior profile and supersensitivity to amphetamine in the C58/J mouse model of autism.

    Science.gov (United States)

    Moy, Sheryl S; Riddick, Natallia V; Nikolova, Viktoriya D; Teng, Brian L; Agster, Kara L; Nonneman, Randal J; Young, Nancy B; Baker, Lorinda K; Nadler, Jessica J; Bodfish, James W

    2014-02-01

    Restricted repetitive behaviors are core symptoms of autism spectrum disorders (ASDs). The range of symptoms encompassed by the repetitive behavior domain includes lower-order stereotypy and self-injury, and higher-order indices of circumscribed interests and cognitive rigidity. Heterogeneity in clinical ASD profiles suggests that specific manifestations of repetitive behavior reflect differential neuropathology. The present studies utilized a set of phenotyping tasks to determine a repetitive behavior profile for the C58/J mouse strain, a model of ASD core symptoms. In an observational screen, C58/J demonstrated overt motor stereotypy, but not over-grooming, a commonly-used measure for mouse repetitive behavior. Amphetamine did not exacerbate motor stereotypy, but had enhanced stimulant effects on locomotion and rearing in C58/J, compared to C57BL/6J. Both C58/J and Grin1 knockdown mice, another model of ASD-like behavior, had marked deficits in marble-burying. In a nose poke task for higher-order repetitive behavior, C58/J had reduced holeboard exploration and preference for non-social, versus social, olfactory stimuli, but did not demonstrate cognitive rigidity following familiarization to an appetitive stimulus. Analysis of available high-density genotype data indicated specific regions of divergence between C58/J and two highly-sociable strains with common genetic lineage. Strain genome comparisons identified autism candidate genes, including Cntnap2 and Slc6a4, located within regions divergent in C58/J. However, Grin1, Nlgn1, Sapap3, and Slitrk5, genes linked to repetitive over-grooming, were not in regions of divergence. These studies suggest that specific repetitive phenotypes can be used to distinguish ASD mouse models, with implications for divergent underlying mechanisms for different repetitive behavior profiles.

  11. "Oh no, not again": representability and a repetitive remark

    Directory of Open Access Journals (Sweden)

    Matt Tierney

    2010-06-01

    Full Text Available

    Abstract (E: In their most repetitive moments, literature and film can help us respond to common critical assumptions about the temporality of trauma. Rather than posit trauma's latency, anteriority, or unrepresentability, I raise questions about its obviousness, interchangeability, and cliché. Moving past trauma theory, and into general questions about repetition and representation, I therefore turn to a phrase that has often been repeated in texts across a range of forms and genres: "Oh no, not again!"

     

    Abstract (F: Lorsqu’ils se font intensément répétitifs, cinéma et littérature  peuvent nous aider à revoir certaines hypoth

  12. Brain signal complexity rises with repetition suppression in visual learning.

    Science.gov (United States)

    Lafontaine, Marc Philippe; Lacourse, Karine; Lina, Jean-Marc; McIntosh, Anthony R; Gosselin, Frédéric; Théoret, Hugo; Lippé, Sarah

    2016-06-21

    Neuronal activity associated with visual processing of an unfamiliar face gradually diminishes when it is viewed repeatedly. This process, known as repetition suppression (RS), is involved in the acquisition of familiarity. Current models suggest that RS results from interactions between visual information processing areas located in the occipito-temporal cortex and higher order areas, such as the dorsolateral prefrontal cortex (DLPFC). Brain signal complexity, which reflects information dynamics of cortical networks, has been shown to increase as unfamiliar faces become familiar. However, the complementarity of RS and increases in brain signal complexity have yet to be demonstrated within the same measurements. We hypothesized that RS and brain signal complexity increase occur simultaneously during learning of unfamiliar faces. Further, we expected alteration of DLPFC function by transcranial direct current stimulation (tDCS) to modulate RS and brain signal complexity over the occipito-temporal cortex. Participants underwent three tDCS conditions in random order: right anodal/left cathodal, right cathodal/left anodal and sham. Following tDCS, participants learned unfamiliar faces, while an electroencephalogram (EEG) was recorded. Results revealed RS over occipito-temporal electrode sites during learning, reflected by a decrease in signal energy, a measure of amplitude. Simultaneously, as signal energy decreased, brain signal complexity, as estimated with multiscale entropy (MSE), increased. In addition, prefrontal tDCS modulated brain signal complexity over the right occipito-temporal cortex during the first presentation of faces. These results suggest that although RS may reflect a brain mechanism essential to learning, complementary processes reflected by increases in brain signal complexity, may be instrumental in the acquisition of novel visual information. Such processes likely involve long-range coordinated activity between prefrontal and lower order visual

  13. Role of repetitive transcranial magnetic stimulation in stroke rehabilitation.

    Science.gov (United States)

    Pinter, Michaela M; Brainin, Michael

    2013-01-01

    In recent years, efforts have focused on investigating the neurophysiological changes that occur in the brain after stroke, and on developing novel strategies such as additional brain stimulation to enhance sensorimotor and cognitive recovery. In the 1990s, repetitive transcranial magnetic stimulation (rTMS) was introduced as a therapeutic tool for improving the efficacy of rehabilitation for recovery after stroke. It is evident that disturbances of interhemispheric processes after stroke result in a pathological hyperactivity of the intact hemisphere. The rationale of using rTMS as a complementary therapy is mainly to decrease the cortical excitability in regions that are presumed to hinder optimal recovery by low-frequency rTMS delivered to the unaffected hemisphere, while high-frequency rTMS delivered to the affected hemisphere facilitates cortical excitability. However, the exact mechanisms of how rTMS works are still under investigation. There is a growing body of research in stroke patients investigating the effect of rTMS on facilitating recovery by modifying cortical and subcortical networks. Clinical trials applying rTMS already yielded promising results in improving recovery of sensorimotor and cognitive functions. Altogether, in combination with conventional therapeutic approaches, rTMS has a potential to become a complementary strategy to enhance stroke recovery by modulating the excitability of targeted brain areas. In future studies, emphasis should be placed on selecting patient populations to determine whether treatment response depends on age, lesion acuteness, or stroke severity. Furthermore, it is important to identify parameters optimizing the beneficial effects of rTMS on stroke recovery, and to monitor their long-term effects.

  14. Knowledge of Repetitions Range Affects Force Production in Trained Females

    Directory of Open Access Journals (Sweden)

    Israel Halperin, Saied J. Aboodarda, Fabien A. Basset, David G. Behm

    2014-12-01

    Full Text Available Most studies have examined pacing strategies with cyclical activities (running and cycling. It has been demonstrated that males employ different pacing strategies during repeated maximal voluntary contractions (MVCs dependent upon a known endpoint. Since different fatiguing mechanisms have been identified between the genders, it is not known if females use comparable pacing strategies. The purpose of this study was to examine if informing female subjects regarding the number of MVCs to perform would affect force and electromyography (EMG. Twenty well-trained females completed 3 fatiguing protocols in a randomized order. In the control condition participants were informed they would perform twelve MVCs and then actually completed twelve. In the unknown condition they were not told how many MVCs to perform but were stopped after twelve. In the deception condition they were initially informed to perform 6 MVCs, but after the 6th MVC they were asked to perform a few more MVCs and were stopped after twelve. During the first 6 MVCs, forces in the deception condition were greater compared to the unknown (p = 0.021, ES = 0.65, 5% and control (p = 0.022, ES = 0.42, 3% conditions. No differences were found between conditions in the last 6 MVCs. A main effect for repetitions showed force deficits during the first 6 MVCs (p = 0.000, ES = 1.81, 13% and last 6 MVCs (p = 0.05, ES = 0.34, 3%. No differences were found between conditions in biceps and triceps EMG. However, EMG decreased during the first 6 MVCs for biceps (p = 0.001, ES = 1.0, 14% and triceps (p = 0.001, ES = 0.76, 14% across conditions. No differences were found in the last 6 MVCs. The anticipation of performing fewer MVCs led to increased force, whereas no endpoint led to decreased force production.

  15. Unconscious Cognition Isn't that Smart: Modulation of Masked Repetition Priming Effect in the Word Naming Task

    Science.gov (United States)

    Kinoshita, Sachiko; Forster, Kenneth I.; Mozer, Michael C.

    2008-01-01

    Masked repetition primes produce greater facilitation in naming in a block containing a high, rather than low proportion of repetition trials. [Bodner, G. E., & Masson, M. E. J. (2004). "Beyond binary judgments: Prime-validity modulates masked repetition priming in the naming task". "Memory & Cognition", 32, 1-11] suggested this phenomenon…

  16. Femtosecond and picosecond laser drilling of metals at high repetition rates and average powers.

    Science.gov (United States)

    Ancona, A; Döring, S; Jauregui, C; Röser, F; Limpert, J; Nolte, S; Tünnermann, A

    2009-11-01

    The influence of pulse duration on the laser drilling of metals at repetition rates of up to 1 MHz and average powers of up to 70 W has been experimentally investigated using an ytterbium-doped-fiber chirped-pulse amplification system with pulses from 800 fs to 19 ps. At a few hundred kilohertz particle shielding causes an increase in the number of pulses for breakthrough, depending on the pulse energy and duration. At higher repetition rates, the heat accumulation effect overbalances particle shielding, but significant melt ejection affects the hole quality. Using femtosecond pulses, heat accumulation starts at higher repetition rates, and the ablation efficiency is higher compared with picosecond pulses.

  17. REPETITIVE MANUAL OPERATIONS IN THE DAIRY SECTOR: ANALYSES AND CRITERIA FOR INTERVENTION

    Directory of Open Access Journals (Sweden)

    Pier Riccardo Porceddu

    2008-03-01

    Full Text Available For the health of workers it is necessary to consider, together with traditional risks (noise, vibrations, microclimate etc., risks deriving from repetitive movements, which can generate muscolo-skeletal disorders. These risks can be found in artisan dairies, where the limited use of machinery and the rapid successive passages for processing the milk require high-frequency repetitive manual movements. The study analysed the risks of repetitive movements for workers in a dairy, using the OCRA method. Various risk-involving operations emerged, which require the re-planning of the workplace. The proposed interventions have not involved high costs for the dairy, or a loss of productivity.

  18. Pulsed pumped Yb-doped fiber amplifier at low repetition rate

    Institute of Scientific and Technical Information of China (English)

    Changgeng Ye; Ping Yan; Mali Gong; Ming Lei

    2005-01-01

    A pulsed pumped Yb-doped double-clad fiber (DCF) master-oscillator power amplifier (MOPA) at low repetition rate is reported. Seeded by a passive Q-switched Nd:YAG microchip laser, the fiber amplifier can generate 167-kW peak-power and 0.83-ns duration pulses at 200-Hz repetition rate. Because of the pulsed pump approach, the amplified spontaneous emission (ASE) and the spurious lasing between pulses are well avoided, and the repetition rate can be set freely from single-shot to 1 kHz. Peak power scaling limitations that arise from the fiber facet damage are discussed.

  19. Repetitive training for ameliorating upper limbs spasm of hemiplegic patients

    Institute of Scientific and Technical Information of China (English)

    Lin Zhu; Lin Liu; Weiqun Song

    2006-01-01

    BACKGROUND:The main aim of rehabilitation is to ameliorate motor function and use the damaged limbs in the activities of daily living.Several factors are needed in the self-recovery of the patients,and the most important one is to reduce spasm.Some mechanical repetitive movements can affect and change the excitability of motor neurons.OBJECTIVE:To observe the effect of repetitive training on ameliorating spasm of upper limbs of hemiplegic patients.DESIGN:A self-controlled observation before and after training.SETTING:Department of Rehabilitation,Xuanwu Hospital of Capital Medical University.PARTICI PANTS: Seven hemiplegic patients induced by brain injury were selected from the Department of Rehabilitation,Xuanwu Hospital,Capital Medical University from March to June in 2005.Inclusive criteria:①Agreed and able to participate in the 30-minute training of hand function; ②Without disturbance of understanding.The patients with aphasia or apraxia,manifestation of shoulder pain,and severe neurological or mental defects.For the 7 patients,the Rivermead motor assessment(RMA)scores ranged 0-10 points,the Rivermead mobility index(RMI)ranged 1-3,and modified Ashworth scale(MAS)was grade 2-4.Their horizontal extension of shoulder joint was 0°-30°,anteflextion was 0°-50°,internal rotation was 50°-90°,external rotation was 0°-10°:and the elbow joint could extend for 15°-135°.METHODS:The viva 2 serial MOTOmed exerciser(Reck Company,Germany)was used.There were three phases of A-B-A.①The phase A lasted for 1 week.The patient sat on a chair facting to the MOTOmed screen.and did the circumduction of upper limbs forwardly,30 minutes a day and 5 days a week.②The phase B lasted for 3 weeks.The training consisted of forward circumduction of upper limbs for 15 minutes.followed by backward ones for 15 minutes and 5-minute rest.③The training in the phase A was performed again for 2 weeks.The extensions of upper limbs were recorded at phase A,the extension and flexion of

  20. Identification of lactic acid bacteria in commercial yogurt and their antibiotic resistance%市售酸奶中乳酸菌的鉴定与耐药性

    Institute of Scientific and Technical Information of China (English)

    秦宇轩; 李晶; 王秋涯; 高可心; 朱宝利; 律娜

    2013-01-01

    [Objective] To identify lactic acid bacteria (LAB) in commercial yogurts and investigate their antibiotic resistance.[Methods] LABs were cultured from 5 yogurt brands and the isolates were identified at the species level by 16S rRNA sequence.Genotyping was performed by repetitive extragenic palindromic PCR (rep-PCR).The sensitivity to 7 antibiotics was tested for all LAB isolates by Kirby-Bauer paper diffusion (K-B method).Meanwhile,9 antibiotic resistance genes(ARGs),including erythromycin resistance genes (ermA and ermB) and tetracycline resistance genes (tetM,tetK,tetS,tetQ,tetO,tetL and tetW),were detected by PCR amplification in the identified LAB isolates.The PCR products were confirmed by sequencing.[Results] Total 100 LABs were isolated,including 23 Lactobacillus delbrueckii ssp.bulgaricus,26 Lactobacillus casei,30 Streptococcus thermophilus,5 Lactobacillus acidophilus,6 Lactobacillus plantarum,and 10 Lactobacillus paracasei.The drug susceptibility test shows that all 100 isolates were resistant to gentamicin and streptomycin,42 isolates were resistant to vancomycin,and on the contrary all were sensitive to cefalexin,erythromycin,tetracycline and oxytetracycline.Moreover,5 ARGs were found in the 28 sequencing confirmed isolates,ermB gene was detected in 8 isolates,tet K in 4 isolates,tetL in 2 isolates,tetM in 4 isolates,tetO in 2 isolates.erm A,tet S,tet Q and tet W genes were not detected in the isolates.Antibiotic resistance genes were found in 53.57% (15/28) sequenced isolates,2-3 antibiotic resistance genes were detected in 4 isolates of L.delbrueckii ssp.bulgaricus.[Conclusions] Some LABs were not labeled in commercial yogurt products.Antibiotic resistance genes tend to be found in the starter culture of L.delbrueckii ssp.Bulgaricus and S.thermophilus.All the LAB isolates were sensitive to erythromycin and tetracycline,even though some carried erythromycin and/or tetracycline resistance genes.We proved again that LAB could carry antibiotic resistance

  1. Repetitive transcranial magnetic stimulation in cervical dystonia: effect of site and repetition in a randomized pilot trial.

    Directory of Open Access Journals (Sweden)

    Sarah Pirio Richardson

    Full Text Available Dystonia is characterized by abnormal posturing due to sustained muscle contraction, which leads to pain and significant disability. New therapeutic targets are needed in this disorder. The objective of this randomized, sham-controlled, blinded exploratory study is to identify a specific motor system target for non-invasive neuromodulation and to evaluate this target in terms of safety and tolerability in the cervical dystonia (CD population. Eight CD subjects were given 15-minute sessions of low-frequency (0.2 Hz repetitive transcranial magnetic stimulation (rTMS over the primary motor cortex (MC, dorsal premotor cortex (dPM, supplementary motor area (SMA, anterior cingulate cortex (ACC and a sham condition with each session separated by at least two days. The Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS score was rated in a blinded fashion immediately pre- and post-intervention. Secondary outcomes included physiology and tolerability ratings. The mean change in TWSTRS severity score by site was 0.25 ± 1.7 (ACC, -2.9 ± 3.4 (dPM, -3.0 ± 4.8 (MC, -0.5 ± 1.1 (SHAM, and -1.5 ± 3.2 (SMA with negative numbers indicating improvement in symptom control. TWSTRS scores decreased from Session 1 (15.1 ± 5.1 to Session 5 (11.0 ± 7.6. The treatment was tolerable and safe. Physiology data were acquired on 6 of 8 subjects and showed no change over time. These results suggest rTMS can modulate CD symptoms. Both dPM and MC are areas to be targeted in further rTMS studies. The improvement in TWSTRS scores over time with multiple rTMS sessions deserves further evaluation.

  2. Combinatorial codon scrambling enables scalable gene synthesis and amplification of repetitive proteins

    Science.gov (United States)

    Tang, Nicholas C.; Chilkoti, Ashutosh

    2016-04-01

    Most genes are synthesized using seamless assembly methods that rely on the polymerase chain reaction (PCR). However, PCR of genes encoding repetitive proteins either fails or generates nonspecific products. Motivated by the need to efficiently generate new protein polymers through high-throughput gene synthesis, here we report a codon-scrambling algorithm that enables the PCR-based gene synthesis of repetitive proteins by exploiting the codon redundancy of amino acids and finding the least-repetitive synonymous gene sequence. We also show that the codon-scrambling problem is analogous to the well-known travelling salesman problem, and obtain an exact solution to it by using De Bruijn graphs and a modern mixed integer linear programme solver. As experimental proof of the utility of this approach, we use it to optimize the synthetic genes for 19 repetitive proteins, and show that the gene fragments are amenable to PCR-based gene assembly and recombinant expression.

  3. Combinatorial codon scrambling enables scalable gene synthesis and amplification of repetitive proteins.

    Science.gov (United States)

    Tang, Nicholas C; Chilkoti, Ashutosh

    2016-04-01

    Most genes are synthesized using seamless assembly methods that rely on the polymerase chain reaction (PCR). However, PCR of genes encoding repetitive proteins either fails or generates nonspecific products. Motivated by the need to efficiently generate new protein polymers through high-throughput gene synthesis, here we report a codon-scrambling algorithm that enables the PCR-based gene synthesis of repetitive proteins by exploiting the codon redundancy of amino acids and finding the least-repetitive synonymous gene sequence. We also show that the codon-scrambling problem is analogous to the well-known travelling salesman problem, and obtain an exact solution to it by using De Bruijn graphs and a modern mixed integer linear programme solver. As experimental proof of the utility of this approach, we use it to optimize the synthetic genes for 19 repetitive proteins, and show that the gene fragments are amenable to PCR-based gene assembly and recombinant expression.

  4. Semantic Integration: Effects of Imagery, Enaction, and Sentence Repetition Training on Prereaders' Recall for Pictograph Sentences.

    Science.gov (United States)

    Ledger, George W.; Ryan, Ellen Bouchard

    1985-01-01

    Over a two-week period, examined the effectiveness of integrative imagery strategy over concrete enaction and repetition strategies for improving kindergartners' recall of pictograph sentences. (Author/BE)

  5. Concept mediation in trilingual translation: evidence from response time and repetition priming patterns.

    Science.gov (United States)

    Francis, Wendy S; Gallard, Sabrina L K

    2005-12-01

    Translation responses to individual words were elicited from 48 English-Spanish-French trilinguals, who translated in six directions at study and two directions at test. Patterns of translation response times and error rates at study reflected the relative proficiency of the trilinguals in comprehension and production of their three languages. At test, repeated items were translated more quickly than new items, with the strongest priming effects occurring for identical repetitions. Repetition priming was also substantial when only the stimulus language or only the response language matched from study to test, implying that repeated comprehension and production processes contribute to priming in translation. Patterns of response times and repetition priming indicate that translation in all directions involved conceptual access. Additive patterns in response time asymmetries and repetition priming were consistent with the treatment of word comprehension and production processes of translation as independent.

  6. Hydrodynamic size distribution of gold nanoparticles controlled by repetition rate during pulsed laser ablation in water

    Science.gov (United States)

    Menéndez-Manjón, Ana; Barcikowski, Stephan

    2011-02-01

    Most investigations on the laser generation and fragmentation of nanoparticles focus on Feret particle size, although the hydrodynamic size of nanoparticles is of great importance, for example in biotechnology for diffusion in living cells, or in engineering, for a tuned rheology of suspensions. In this sense, the formation and fragmentation of gold colloidal nanoparticles using femtosecond laser ablation at variable pulse repetition rates (100-5000 Hz) in deionized water were investigated through their plasmon resonance and hydrodynamic diameter, measured by Dynamic Light Scattering. The increment of the repetition rate does not influence the ablation efficiency, but produces a decrease of the hydrodynamic diameter and blue-shift of the plasmon resonance of the generated gold nanoparticles. Fragmentation, induced by inter-pulse irradiation of the colloids was measured online, showing to be more effective low repetition rates. The pulse repetition rate is shown to be an appropriate laser parameter for hydrodynamic size control of nanoparticles without further influence on the production efficiency.

  7. High Energy Single Frequency Fiber Laser at Low Repetition Rate Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR phase II project proposes a single frequency high energy fiber laser system operating at low repetition rate of 10 Hz to 1 kHz for coherent Lidar systems...

  8. One-way sequencing of multiple amplicons from tandem repetitive mitochondrial DNA control region.

    Science.gov (United States)

    Xu, Jiawu; Fonseca, Dina M

    2011-10-01

    Repetitive DNA sequences not only exist abundantly in eukaryotic nuclear genomes, but also occur as tandem repeats in many animal mitochondrial DNA (mtDNA) control regions. Due to concerted evolution, these repetitive sequences are highly similar or even identical within a genome. When long repetitive regions are the targets of amplification for the purpose of sequencing, multiple amplicons may result if one primer has to be located inside the repeats. Here, we show that, without separating these amplicons by gel purification or cloning, directly sequencing the mitochondrial repeats with the primer outside repetitive region is feasible and efficient. We exemplify it by sequencing the mtDNA control region of the mosquito Aedes albopictus, which harbors typical large tandem DNA repeats. This one-way sequencing strategy is optimal for population surveys.

  9. Multiple Description Spherical Quantization of Sinusoidal Parameters with Repetition Coding of the Amplitudes

    DEFF Research Database (Denmark)

    Jensen, Jesper Rindom; Christensen, Mads Græsbøll; Larsen, Morten Holm

    2009-01-01

    Recently, multiple description spherical trellis-coded quantization (MDSTCQ) for quantization of sinusoidal parameters was proposed, which suffered from a suboptimal implementation. Therefore, we propose the multiple description spherical quantization with repetition coding of the amplitudes (MDS...

  10. Evaluation of Na+/K+ pump function following repetitive activity in mouse peripheral nerve

    DEFF Research Database (Denmark)

    Moldovan, Mihai; Krarup, Christian

    2006-01-01

    excitability measures simultaneously from the evoked plantar compound muscle action potential (CMAP) and sciatic compound nerve action potential (CNAP). Three minutes after repetitive supramaximal stimulation maximal CMAP and CNAP amplitudes recovered but the threshold was increased approximately 40% for motor...

  11. pRB Takes an EZ Path to a Repetitive Task.

    Science.gov (United States)

    Sanidas, Ioannis; Dyson, Nicholas J

    2016-12-15

    Repetitive DNA elements are essential for genome function; in this issue of Molecular Cell, Ishak et al. (2016) describe a novel mechanism of epigenetic repression at these elements that requires pRB-dependent recruitment of EZH2.

  12. Stability of Closed Loop Controlled Repetitive Periodic System applied to control of CD-Player

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob; Andersen, Palle

    2005-01-01

    In this paper a criterion for stability of specific control scheme for handling linear dynamic control systems with repetitive periodic sensor faults is derived. The given system and control scheme are described and defined. By combining these with the lifting technique a necessary and sufficient...... the repetitive sensor faults (surface faults). The fault approximations are subsequently subtracted from the measurements, and the influence from these repetitive sensor faults are thereby removed from the computed control signals....... stability criterion is derived. This criterion is following applied to an example on a feature based control scheme for handling CD-players playing CDs with surface faults. This feature based control scheme is handling repetitive periodic sensor faults. The feature based control scheme approximates...

  13. Repetitive control mechanism of disturbance cancellation using a hybrid regression and genetic algorithm

    Science.gov (United States)

    Lin, Jeng-Wen; Shen, Pu Fun; Wen, Hao-Ping

    2015-10-01

    The application of a repetitive control mechanism for use in a mechanical control system has been a topic of investigation. The fundamental purpose of repetitive control is to eliminate disturbances in a mechanical control system. This paper presents two different repetitive control laws using individual types of basis function feedback and their combinations. These laws adjust the command given to a feedback control system to eliminate tracking errors, generally resulting from periodic disturbance. Periodic errors can be reduced through linear basis functions using regression and a genetic algorithm. The results illustrate that repetitive control is most effective method for eliminating disturbances. When the data are stabilized, the tracking error of the obtained convergence value, 10-14, is the optimal solution, verifying that the proposed regression and genetic algorithm can satisfactorily reduce periodic errors.

  14. Repetitive negative thinking and suicide: a burgeoning literature with need for further exploration.

    Science.gov (United States)

    Law, Keyne C; Tucker, Raymond P

    2017-08-24

    Extant research has found a significant overlap between various repetitive negative thinking (RNT) patterns, such as rumination and worry, across different affective disorders implicating that the process of repetitive negative thinking is likely trans-diagnostic. Furthermore, RNT patterns at the core of psychiatric disorders associated with suicide (e.g., rumination and worry) have been found to be associated with suicide even after accounting for the disorder. A synthesis of existing literature on repetitive negative thoughts suggest that following negative emotional experiences, RNTs may lead to a sense of entrapment and hopelessness that may contribute to the onset of suicidal ideation and then facilitate the transition from thinking about suicide to making a suicide attempt by increasing an individual's capability for suicide through repetitive exposure to violent thoughts and imagery associated with suicide. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. An evaluation of factors affecting duration of treatment with repetitive transcranial magnetic stimulation for depression

    Directory of Open Access Journals (Sweden)

    Roni Broder Cohen

    2007-12-01

    Full Text Available Objective: To investigate the effects of repetitive transcranialmagnetic stimulation in patients with major depression who weresubmitted to this treatment during the period from 2000 to 2006.Methods: A retrospective study with 204 patients who underwenttreatment with repetitive transcranial magnetic stimulation, collectingdata from those who experienced remission (defined as a HDRS scoreequal to or lower than 7. The patients were followed for up to 6 monthsafter treatment. Mean duration of remission for this cohort of patientswas 70.2 (± 58.4 days. Results: The only variable associated withthe duration of remission in the linear regression model was numberof repetitive transcranial magnetic stimulation sessions. Conclusion:Our findings suggest that the greater the number of sessions, the longerthe duration of repetitive transcranial magnetic stimulation effects.Consequently, future research investigating the effects of repetitivetranscranial magnetic stimulation should explore this variable in orderto maximize the therapeutic effects of this new brain stimulationtechnique.

  16. Evidence-based guidelines on the therapeutic use of repetitive transcranial magnetic stimulation (rTMS)

    DEFF Research Database (Denmark)

    Lefaucheur, Jean-Pascal; André-Obadia, Nathalie; Antal, Andrea

    2014-01-01

    A group of European experts was commissioned to establish guidelines on the therapeutic use of repetitive transcranial magnetic stimulation (rTMS) from evidence published up until March 2014, regarding pain, movement disorders, stroke, amyotrophic lateral sclerosis, multiple sclerosis, epilepsy...

  17. Transduction of Repetitive Mechanical Stimuli by Piezo1 and Piezo2 Ion Channels

    Directory of Open Access Journals (Sweden)

    Amanda H. Lewis

    2017-06-01

    Full Text Available Several cell types experience repetitive mechanical stimuli, including vein endothelial cells during pulsating blood flow, inner ear hair cells upon sound exposure, and skin cells and their innervating dorsal root ganglion (DRG neurons when sweeping across a textured surface or touching a vibrating object. While mechanosensitive Piezo ion channels have been clearly implicated in sensing static touch, their roles in transducing repetitive stimulations are less clear. Here, we perform electrophysiological recordings of heterologously expressed mouse Piezo1 and Piezo2 responding to repetitive mechanical stimulations. We find that both channels function as pronounced frequency filters whose transduction efficiencies vary with stimulus frequency, waveform, and duration. We then use numerical simulations and human disease-related point mutations to demonstrate that channel inactivation is the molecular mechanism underlying frequency filtering and further show that frequency filtering is conserved in rapidly adapting mouse DRG neurons. Our results give insight into the potential contributions of Piezos in transducing repetitive mechanical stimuli.

  18. Garnet composite films with Au particles fabricated by repetitive formation for enhancement of Faraday effect

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, H; Nakai, Y [Department of Electronics and Intelligent Systems, Tohoku Institute of Technology, 35-1 Yagiyama-Kasumi, Taihaku, Sendai, Miyagi 982-8577 (Japan); Mizutani, Y; Inoue, M [Department of Electrical and Electronic Information Engineering, Toyohashi University of Technology, Tempaku, Toyohashi, Aichi 441-8580 (Japan); Fedyanin, A A, E-mail: uchida_hn@tohtech.ac.jp [Faculty of Physics, Moscow State University, Moscow 119992 (Russian Federation)

    2011-02-16

    To prepare garnet (Bi : YIG) composite films with Au particles, we used a repetitive formation method to increase the number density of particles. On increasing the number of repetitions, the diameter distribution of the particles changed. After five repetitions using 5 nm Au films, the diameter distribution separated into two size groups. Shift of wavelength-excited localized surface plasmon resonance is discussed relative to the diameter distribution. In the composite films, enhancement of Faraday rotation associated with surface plasmons was observed. With six repetitions, a maximum enhanced rotation of -1.2{sup 0} was obtained, which is 20 times larger than that of a single Bi : YIG film. The figures of merit for the composite films are discussed. The thickness of a Bi : YIG composite film working for enhanced Faraday rotation was examined using an ion milling method.

  19. Restricted and repetitive behaviours, sensory processing and cognitive style in children with autism spectrum disorders.

    Science.gov (United States)

    Chen, Yu-Han; Rodgers, Jacqui; McConachie, Helen

    2009-04-01

    Many individuals with autism tend to focus on details. It has been suggested that this cognitive style may underlie the presence of stereotyped routines, repetitive interests and behaviours, and both relate in some way to sensory abnormalities. Twenty-nine children with diagnosis of high functioning autism or Asperger syndrome completed the Embedded Figures Test (EFT), and their parents the Short Sensory Profile and Childhood Routines Inventory. Significant correlations were found between degree of sensory abnormalities and amount of restricted and repetitive behaviours reported. Repetitive behaviours, age and IQ significantly predicted completion time on the EFT. The results suggest a cognitive link between an individual's detail-focused cognitive style and their repetitiveness. No such relationship was found with sensory processing abnormalities, which may arise at a more peripheral level of functioning.

  20. DC high voltage to drive helium plasma jet comprised of repetitive streamer breakdowns

    CERN Document Server

    Wang, Xingxing

    2016-01-01

    This paper demonstrates and studies helium atmospheric pressure plasma jet comprised of series of repetitive streamer breakdowns, which is driven by a pure DC high voltage (auto-oscillations). Repetition frequency of the breakdowns is governed by the geometry of discharge electrodes/surroundings and gas flow rate. Each next streamer is initiated when the electric field on the anode tip recovers after the previous breakdown and reaches the breakdown threshold value of about 2.5 kV/cm. Repetition frequency of the streamer breakdowns excited using this principle can be simply tuned by reconfiguring the discharge electrode geometry. This custom-designed type of the helium plasma jet, which operates on the DC high voltage and is comprised of the series of the repetitive streamer breakdowns at frequency about 13 kHz, is demonstrated.

  1. Repetition rate tunable ultra-short optical pulse generation based on electrical pattern generator

    Institute of Scientific and Technical Information of China (English)

    Xin Fu; Hongming Zhang; Meng Yan; Minyu Yao

    2009-01-01

    @@ An actively mode-locked laser with tunable repetition rate is proposed and experimentally demonstrated based on a programmable electrical pattern generator.By changing the repetition rate of the electrical patterns applied on the in-cavity modulator, the repetition rate of the output optical pulse sequences changes accordingly while the pulse width of the optical pulse train remains almost constant.In other words, the output ultra-short pulse train has a tunable duty cycle.In a proof-of-principle experiment, optical pulses with repetition rates of 10, 5, 2.5 and 1.25 GHz are obtained by adjusting the electrical pattern applied on the in-cavity modulator while their pulse widths remain almost unchanged.

  2. Widespread Chromatin Accessibility at Repetitive Elements Links Stem Cells with Human Cancer

    Directory of Open Access Journals (Sweden)

    Nicholas C. Gomez

    2016-11-01

    Full Text Available Chromatin regulation is critical for differentiation and disease. However, features linking the chromatin environment of stem cells with disease remain largely unknown. We explored chromatin accessibility in embryonic and multipotent stem cells and unexpectedly identified widespread chromatin accessibility at repetitive elements. Integrating genomic and biochemical approaches, we demonstrate that these sites of increased accessibility are associated with well-positioned nucleosomes marked by distinct histone modifications. Differentiation is accompanied by chromatin remodeling at repetitive elements associated with altered expression of genes in relevant developmental pathways. Remarkably, we found that the chromatin environment of Ewing sarcoma, a mesenchymally derived tumor, is shared with primary mesenchymal stem cells (MSCs. Accessibility at repetitive elements in MSCs offers a permissive environment that is exploited by the critical oncogene responsible for this cancer. Our data demonstrate that stem cells harbor a unique chromatin landscape characterized by accessibility at repetitive elements, a feature associated with differentiation and oncogenesis.

  3. Interspecific "common" repetitive DNA sequences in salamanders of the genus Plethodon.

    Science.gov (United States)

    Mizuno, S; Andrews, C; Macgregor, H C

    1976-10-12

    Intermediate repetitive sequences of Plethodon cinereus which comprised about 30% of the genomic DNA were isolated and iodinated with 125I. About 5% of the 125I-repetitive fraction hybridized with a large excess of DNA from P. dunni at Cot 20. About half of the 125I-DNA in the hybrids was resistant to extensive digestion with S-1 nuclease. The average molecular size of the S-1 nuclease-resistant fraction was about 100 nucleotide pairs. The melting temperature of the S-1 nuclease-resistant fraction was about 2 degrees lower than that of the corresponding fraction made with P. cinereus DNA. These results are taken to indicate the presence in the genomes of P. cinereus and P. dunni of evolutionarily stable "common" repetitive sequences. The average frequency of repetition of the common repetitive sequences is about 6,000 X in both species. The common repetitive fraction is also present in the genomes of other species of Plethodon, although the general populations of intermediate repetitive sequences are markedly different from one species to another. The cinereus--dunni common repetitive sequences could not be detected in plethodontids belonging to different tribes, nor in more distantly related amphibians. The profiles of binding of the common repetitive sequences to CsCl or CS2SO4-Ag+ density gradient fractions of P. dunni DNA suggested that these sequences consisted of heterogeneous components with respect to base compositions, and that they did not include large amounts of the genes for ribosomal RNA, 5S RNA, 4S RNA, or histone messenger RNA. In situ hybridization of the 3H-labelled intermediate repetitive sequences of P. cinereus to male meiotic chromosomes of the same species gave autoradiographs after an exposure of seven days showing all 14 chromosomes labelled. The pattern of labelling appeared not to be random, but was impossible to analyse on account of the irregular shapes and different degrees of stretching of diplotene and prometaphase chromosomes. In

  4. Bilingual performance on nonword repetition in Spanish and English.

    Science.gov (United States)

    Summers, Connie; Bohman, Thomas M; Gillam, Ronald B; Peña, Elizabeth D; Bedore, Lisa M

    2010-01-01

    Nonword repetition (NWR) involves the ability to perceive, store, recall and reproduce phonological sequences. These same abilities play a role in word and morpheme learning. Cross-linguistic studies of performance on NWR tasks, word learning, and morpheme learning yield patterns of increased performance on all three tasks as a function of age and language experience. These results are consistent with the idea that there may be universal information-processing mechanisms supporting language learning. Because bilingual children's language experience is divided across two languages, studying performance in two languages on NWR could inform one's understanding of the relationship between information processing and language learning. The primary aims of this study were to compare bilingual language learners' recall of Spanish-like and English-like items on NWR tasks and to assess the relationships between performance on NWR, semantics, and morphology tasks. Sixty-two Hispanic children exposed to English and Spanish were recruited from schools in central Texas, USA. Their parents reported on the children's input and output in both languages. The children completed NWR tasks and short tests of semantics and morphosyntax in both languages. Mixed-model analysis of variance was used to explore direct effects and interactions between the variables of nonword length, language experience, language outcome measures, and cumulative exposure on NWR performance. Children produced the Spanish-like nonwords more accurately than the English-like nonwords. NWR performance was significantly correlated to cumulative language experience in both English and Spanish. There were also significant correlations between NWR and morphosyntax but not semantics. Language knowledge appears to play a role in the task of NWR. The relationship between performance on morphosyntax and NWR tasks indicates children rely on similar language-learning mechanisms to mediate these tasks. More exposure to

  5. Risk of repetition of suicide attempt, suicide or all deaths after an episode of attempted suicide

    DEFF Research Database (Denmark)

    Christiansen, Erik; Jensen, Børge Frank

    2007-01-01

    This study was undertaken in order to estimate the incidence of repetition of suicide attempt, suicide and all deaths, and to analyse the influence of psychiatric illness and socio-demographic factors on these.......This study was undertaken in order to estimate the incidence of repetition of suicide attempt, suicide and all deaths, and to analyse the influence of psychiatric illness and socio-demographic factors on these....

  6. Use of Long-Range Repetitive Element Polymorphism-PCR To Differentiate Bacillus anthracis Strains

    OpenAIRE

    Brumlik, Michael J.; Szymajda, Urszula; Zakowska, Dorota; Liang, Xudong; Redkar, Rajendra J.; Patra, Guy; Del Vecchio, Vito G.

    2001-01-01

    The genome of Bacillus anthracis is extremely monomorphic, and thus individual strains have often proven to be recalcitrant to differentiation at the molecular level. Long-range repetitive element polymorphism-PCR (LR REP-PCR) was used to differentiate various B. anthracis strains. A single PCR primer derived from a repetitive DNA element was able to amplify variable segments of a bacterial genome as large as 10 kb. We were able to characterize five genetically distinct groups by examining 10...

  7. Femtosecond Ti:sapphire cryogenic amplifier with high gain and MHz repetition rate.

    Science.gov (United States)

    Dantan, Aurélien; Laurat, Julien; Ourjoumtsev, Alexei; Tualle-Brouri, Rosa; Grangier, Philippe

    2007-07-09

    We demonstrate high gain amplification of 160-femtosecond pulses in a compact double-pass cryogenic Ti:sapphire amplifier. The setup involves a negative GVD mirrors recompression stage, and operates with a repetition rate between 0.2 and 4 MHz with a continuous pump laser. Amplification factors as high as 17 and 320 nJ Fourier-limited pulses are obtained at a 800 kHz repetition rate.

  8. Optical beam dynamics in a gas repetitively heated by femtosecond filaments

    CERN Document Server

    Jhajj, N; Wahlstrand, J K; Milchberg, H M

    2013-01-01

    We investigate beam pointing dynamics in filamentation in gases driven by high repetition rate femtosecond laser pulses. Upon suddenly exposing a gas to a kilohertz train of filamenting pulses, the filament is steered from its original direction to a new stable direction whose equilibrium is determined by a balance among buoyant, viscous, and diffusive processes in the gas. Results are shown for Xe and air, but are broadly applicable to all configurations employing high repetition rate femtosecond laser propagation in gases.

  9. High repetition rate femtosecond dye amplifier using a laser diode pumped neodymium:YAG laser

    Energy Technology Data Exchange (ETDEWEB)

    Zysset, B.; LaGasse, M.J.; Fujimoto, J.G.; Kafka, J.D.

    1989-02-06

    A high repetition rate femtosecond dye amplifier is demonstrated using a laser diode pumped Q-switched Nd:YAG laser. Amplification of wavelength tunable 300 fs pulses from a synchronously mode-locked rhodamine dye laser is achieved with a saturated gain of 70 and a small gain of 200 at a repetition rate of 800 Hz. Maximum pulse energies of 40 nJ are obtained, and pulse compression to as short as 30 fs is demonstrated.

  10. High repetition rate femtosecond dye amplifier using a laser diode pumped neodymium:YAG laser

    Science.gov (United States)

    Zysset, B.; LaGasse, M. J.; Fujimoto, J. G.; Kafka, J. D.

    1989-02-01

    A high repetition rate femtosecond dye amplifier is demonstrated using a laser diode pumped Q-switched Nd:YAG laser. Amplification of wavelength tunable 300 fs pulses from a synchronously mode-locked rhodamine dye laser is achieved with a saturated gain of 70 and a small gain of 200 at a repetition rate of 800 Hz. Maximum pulse energies of 40 nJ are obtained, and pulse compression to as short as 30 fs is demonstrated.

  11. Repetitive speech elicits widespread deactivation in the human cortex: the “Mantra” effect?

    Science.gov (United States)

    Berkovich-Ohana, Aviva; Wilf, Meytal; Kahana, Roni; Arieli, Amos; Malach, Rafael

    2015-01-01

    Background Mantra (prolonged repetitive verbal utterance) is one of the most universal mental practices in human culture. However, the underlying neuronal mechanisms that may explain its powerful emotional and cognitive impact are unknown. In order to try to isolate the effect of silent repetitive speech, which is used in most commonly practiced Mantra meditative practices, on brain activity, we studied the neuronal correlates of simple repetitive speech in nonmeditators – that is, silent repetitive speech devoid of the wider context and spiritual orientations of commonly practiced meditation practices. Methods We compared, using blood oxygenated level-dependent (BOLD) functional magnetic resonance imaging (fMRI), a simple task of covertly repeating a single word to resting state activity, in 23 subjects, none of which practiced meditation before. Results We demonstrate that the repetitive speech was sufficient to induce a widespread reduction in BOLD signal compared to resting baseline. The reduction was centered mainly on the default mode network, associated with intrinsic, self-related processes. Importantly, contrary to most cognitive tasks, where cortical-reduced activation in one set of networks is typically complemented by positive BOLD activity of similar magnitude in other cortical networks, the repetitive speech practice resulted in unidirectional negative activity without significant concomitant positive BOLD. A subsequent behavioral study showed a significant reduction in intrinsic thought processes during the repetitive speech condition compared to rest. Conclusions Our results are compatible with a global gating model that can exert a widespread induction of negative BOLD in the absence of a corresponding positive activation. The triggering of a global inhibition by the minimally demanding repetitive speech may account for the long-established psychological calming effect associated with commonly practiced Mantra-related meditative practices. PMID

  12. Neuronal mechanisms and circuits underlying repetitive behaviors in mouse models of autism spectrum disorder

    OpenAIRE

    Kim, Hyopil; Lim, Chae-Seok; Kaang, Bong-Kiun

    2016-01-01

    Autism spectrum disorder (ASD) refers to a broad spectrum of neurodevelopmental disorders characterized by three central behavioral symptoms: impaired social interaction, impaired social communication, and restricted and repetitive behaviors. However, the symptoms are heterogeneous among patients and a number of ASD mouse models have been generated containing mutations that mimic the mutations found in human patients with ASD. Each mouse model was found to display a unique set of repetitive b...

  13. Relationship between postural control and restricted, repetitive behaviors in autism spectrum disorders

    OpenAIRE

    Krestin eRadonovich; Fournier, Kimberly A.; Christopher J. Hass

    2013-01-01

    Restricted, repetitive behaviors (RRBs) are one of the core diagnostic criteria of autism spectrum disorders (ASD), and include simple repetitive motor behaviors and more complex cognitive behaviors, such as compulsions and restricted interests. In addition to the core symptoms, impaired movement is often observed in ASD. Research suggests that the postural system in individuals with ASD is immature and may never reach adult levels. RRBs have been related to postural sway in individuals with...

  14. Outcomes in spasticity after repetitive transcranial magnetic and transcranial direct current stimulations

    OpenAIRE

    Gunduz, Aysegul; Kumru, Hatice; Pascual-Leone, Alvaro

    2014-01-01

    Non-invasive brain stimulations mainly consist of repetitive transcranial magnetic stimulation and transcranial direct current stimulation. Repetitive transcranial magnetic stimulation exhibits satisfactory outcomes in improving multiple sclerosis, stroke, spinal cord injury and cerebral palsy-induced spasticity. By contrast, transcranial direct current stimulation has only been studied in post-stroke spasticity. To better validate the efficacy of non-invasive brain stimulations in improving ...

  15. Facilitating memory for novel characters by reducing neural repetition suppression in the left fusiform cortex.

    Directory of Open Access Journals (Sweden)

    Gui Xue

    Full Text Available BACKGROUND: The left midfusiform and adjacent regions have been implicated in processing and memorizing familiar words, yet its role in memorizing novel characters has not been well understood. METHODOLOGY/PRINCIPAL FINDINGS: Using functional MRI, the present study examined the hypothesis that the left midfusiform is also involved in memorizing novel characters and spaced learning could enhance the memory by enhancing the left midfusiform activity during learning. Nineteen native Chinese readers were scanned while memorizing the visual form of 120 Korean characters that were novel to the subjects. Each character was repeated four times during learning. Repetition suppression was manipulated by using two different repetition schedules: massed learning and spaced learning, pseudo-randomly mixed within the same scanning session. Under the massed learning condition, the four repetitions were consecutive (with a jittered inter-repetition interval to improve the design efficiency. Under the spaced learning condition, the four repetitions were interleaved with a minimal inter-repetition lag of 6 stimuli. Spaced learning significantly improved participants' performance during the recognition memory test administered one hour after the scan. Stronger left midfusiform and inferior temporal gyrus activities during learning (summed across four repetitions were associated with better memory of the characters, based on both within- and cross-subjects analyses. Compared to massed learning, spaced learning significantly reduced neural repetition suppression and increased the overall activities in these regions, which were associated with better memory for novel characters. CONCLUSIONS/SIGNIFICANCE: These results demonstrated a strong link between cortical activity in the left midfusiform and memory for novel characters, and thus challenge the visual word form area (VWFA hypothesis. Our results also shed light on the neural mechanisms of the spacing effect in

  16. Accurate Prediction of the Statistics of Repetitions in Random Sequences: A Case Study in Archaea Genomes.

    Science.gov (United States)

    Régnier, Mireille; Chassignet, Philippe

    2016-01-01

    Repetitive patterns in genomic sequences have a great biological significance and also algorithmic implications. Analytic combinatorics allow to derive formula for the expected length of repetitions in a random sequence. Asymptotic results, which generalize previous works on a binary alphabet, are easily computable. Simulations on random sequences show their accuracy. As an application, the sample case of Archaea genomes illustrates how biological sequences may differ from random sequences.

  17. High-efficiency synthesis of nanoparticles in a repetitive multigap spark discharge generator

    Science.gov (United States)

    Ivanov, V. V.; Efimov, A. A.; Mylnikov, D. A.; Lizunova, A. A.; Bagazeev, A. V.; Beketov, I. V.; Shcherbinin, S. V.

    2016-08-01

    We describe a method of obtaining aerosol nanoparticles in a repetitive spark discharge generator with 12 interelectrode gaps between tin electrodes, which operates at a pulse repetition frequency of 2.5 kHz. During synthesis of tin oxide nanoparticles in air, the mass productivity of the gas discharge generator reaches up to 9 g/h for primary particles with characteristic sizes within 5-10 nm and agglomerate size on the order of 50 nm.

  18. Coupling coefficient for TEA CO2 laser propulsion with variable pulse repetition rate

    Institute of Scientific and Technical Information of China (English)

    Yijun Zheng; Rongqing Tan; Donglei Wang; Guang Zheng; Changjun Ke; Kuohai Zhang; Chongyi Wan; Jin Wu

    2006-01-01

    @@ Because pulse repetition rate affected directly the momentum coupling coefficient of transversely excited atmospheric (TEA) CO2 laser propulsion, a double pulse trigger, controlling high voltage switch of laser excitation circuit, was designed. The pulse interval ranged between 5 and 100 ms. The momentum coupling coefficient for air-breathing mode laser propulsion was studied experimentally. It was found that the momentum coupling coefficient decreased with the pulse repetition rate increasing.

  19. Liking and wanting pleasant odors: different effects of repetitive exposure in men and women

    OpenAIRE

    Chantal eTriscoli; Ilona eCroy; Håkan eOlausson; Uta eSailer

    2014-01-01

    Odors can enrich the perception of our environment and are commonly used to attract people in marketing situations. However, the perception of an odor changes over repetitions. This study investigated whether repetitive exposition to olfactory stimuli leads to a change in the perceived pleasantness (“liking”) or in the wish to be further exposed to the same olfactory stimulus (“wanting”), and whether these two mechanisms show gender differences. Three different pleasant odors were each repeat...

  20. Repetitive Cyclic Potentiodynamic Polarization Scan Results for Reduced Sample Volume Testing

    Energy Technology Data Exchange (ETDEWEB)

    LaMothe, Margaret E. [Washington River Protection Solutions, Richland, WA (United States)

    2016-03-15

    This report is the compilation of data gathered after repetitively testing simulated tank waste and a radioactive tank waste sample using a cyclic potentiodynamic polarization (CPP) test method to determine corrosion resistance of metal samples. Electrochemistry testing of radioactive tank samples is often used to assess the corrosion susceptibility and material integrity of waste tank steel. Repetitive testing of radiological tank waste is occasionally requested at 222-S Laboratory due to the limited volume of radiological tank sample received for testing.

  1. How to improve repetition ability in patients with Wernicke's aphasia: the effect of a disguised task.

    Science.gov (United States)

    Otsuki, M; Soma, Y; Yoshimura, N; Miyashita, K; Nagatsuka, K; Naritomi, H

    2005-05-01

    Dissociation "automatico-voluntaire" is a symptom observed in aphasic patients. We elucidated the difference between voluntary and involuntary speech output in a quantitative manner using the same task materials in nine patients with Wernicke's aphasia. All the patients exhibited better ability and less paraphasias in a repetition task elicited in a disguised condition than in an ordinary repetition condition. This result indicates that the output difficulty in Wernicke's aphasia might be a disability of volitional control over the language system.

  2. Nonword Repetition and Vocabulary Knowledge as Predictors of Children's Phonological and Semantic Word Learning.

    Science.gov (United States)

    Adlof, Suzanne M; Patten, Hannah

    2017-03-01

    This study examined the unique and shared variance that nonword repetition and vocabulary knowledge contribute to children's ability to learn new words. Multiple measures of word learning were used to assess recall and recognition of phonological and semantic information. Fifty children, with a mean age of 8 years (range 5-12 years), completed experimental assessments of word learning and norm-referenced assessments of receptive and expressive vocabulary knowledge and nonword repetition skills. Hierarchical multiple regression analyses examined the variance in word learning that was explained by vocabulary knowledge and nonword repetition after controlling for chronological age. Together with chronological age, nonword repetition and vocabulary knowledge explained up to 44% of the variance in children's word learning. Nonword repetition was the stronger predictor of phonological recall, phonological recognition, and semantic recognition, whereas vocabulary knowledge was the stronger predictor of verbal semantic recall. These findings extend the results of past studies indicating that both nonword repetition skill and existing vocabulary knowledge are important for new word learning, but the relative influence of each predictor depends on the way word learning is measured. Suggestions for further research involving typically developing children and children with language or reading impairments are discussed.

  3. Longer repetition duration increases muscle activation and blood lactate response in matched resistance training protocols

    Directory of Open Access Journals (Sweden)

    Hugo Cesar Martins-Costa

    2016-03-01

    Full Text Available Abstract This study analyzed the effect of different repetition durations on electromyographic and blood lactate responses of the bench press exercise. Fifteen recreationally trained male volunteers completed two training protocols, matched for intensity (% one-repetition maximum; 1RM, number of sets, number of repetitions, and rest intervals. One of the protocols was performed with a repetition duration of 4 s (2 s concentric: 2 s eccentric; 2:2 protocol, whereas the second protocol had a repetition duration of 6 s (2 s concentric: 4 s eccentric; 2:4 protocol. The results showed higher normalized integrated electromyography (pectoralis major and triceps brachii for the 2:4 protocol. Blood lactate concentration was also higher in the 2:4 protocol across all sets. These results show that adding 2 s to the eccentric action in matched training protocols increases muscle activation and blood lactate response, which reinforces the notion that increasing repetition duration is an alternative load progression in resistance training.

  4. Effect of repetition proportion on language-driven anticipatory eye movements

    Science.gov (United States)

    Britt, Allison E.; Mirman, Daniel; Kornilov, Sergey A.; Magnuson, James S.

    2014-01-01

    Previous masked priming research in word recognition has demonstrated that repetition priming is influenced by experiment-wise information structure, such as proportion of target repetition. Research using naturalistic tasks and eye-tracking has shown that people use linguistic knowledge to anticipate upcoming words. We examined whether the proportion of target repetition within an experiment can have a similar effect on anticipatory eye movements. We used a word-to-picture matching task (i.e., the visual world paradigm) with target repetition proportion carefully controlled. Participants’ eye movements were tracked starting when the pictures appeared, one second prior to the onset of the target word. Targets repeated from the previous trial were fixated more than other items during this preview period when target repetition proportion was high and less than other items when target repetition proportion was low. These results indicate that linguistic anticipation can be driven by short-term within-experiment trial structure, with implications for the generalization of priming effects, the bases of anticipatory eye movements, and experiment design. PMID:24345674

  5. A feasible repetitive transcranial magnetic stimulation clinical protocol in migraine prevention

    Directory of Open Access Journals (Sweden)

    Shawn Zardouz

    2016-10-01

    Full Text Available Objective: This case series was conducted to determine the clinical feasibility of a repetitive transcranial magnetic stimulation protocol for the prevention of migraine (with and without aura. Methods: Five patients with migraines underwent five repetitive transcranial magnetic stimulation sessions separated in 1- to 2-week intervals for a period of 2 months at a single tertiary medical center. Repetitive transcranial magnetic stimulation was applied to the left motor cortex with 2000 pulses (20 trains with 1s inter-train interval delivered per session, at a frequency of 10 Hz and 80% resting motor threshold. Pre- and post-treatment numerical rating pain scales were collected, and percent reductions in intensity, frequency, and duration were generated. Results: An average decrease in 37.8%, 32.1%, and 31.2% were noted in the intensity, frequency, and duration of migraines post-repetitive transcranial magnetic stimulation, respectively. A mean decrease in 1.9±1.0 (numerical rating pain scale ± standard deviation; range: 0.4–2.8 in headache intensity scores was noted after the repetitive transcranial magnetic stimulation sessions. Conclusion: The tested repetitive transcranial magnetic stimulation protocol is a well-tolerated, safe, and effective method for migraine prevention.

  6. Motivational salience modulates hippocampal repetition suppression and functional connectivity in humans

    Directory of Open Access Journals (Sweden)

    Sarah eZweynert

    2011-11-01

    Full Text Available Repetition suppression (RS is a rapid decrease of stimulus-related neuronal responses upon repeated presentation of a stimulus. Previous studies have demonstrated that negative emotional salience of stimuli enhances RS. It is, however, unclear how motivational salience of stimuli, such as reward-predicting value, influences RS for complex visual stimuli, and which brain regions might show differences in RS for reward-predicting and neutral stimuli. Here we investigated the influence of motivational salience on RS of complex scenes using event-related fMRI. Thirty young healthy volunteers performed a monetary incentive delay (MID task with complex scenes (indoor vs. outdoor serving as neutral or reward-predicting cue pictures. Each cue picture was presented three times. In line with previous findings, reward anticipation was associated with activations in the ventral striatum, midbrain, and orbitofrontal cortex (OFC. Stimulus repetition was associated with pronounced repetition suppression in ventral visual stream areas like the parahippocampal place area (PPA. An interaction of reward anticipation and repetition suppression was specifically observed in the anterior hippocampus, where a response decrease across repetitions was observed for the reward-predicting scenes only. Functional connectivity analysis further revealed specific activity-dependent connectivity increases of the hippocampus and the PPA and OFC. Our results suggest that hippocampal repetition suppression is sensitive to reward-predicting properties of stimuli and might therefore reflect a rapid, adaptive neural response mechanism for motivationally salient information.

  7. Self-organization of repetitive spike patterns in developing neuronal networks in vitro.

    Science.gov (United States)

    Sun, Jyh-Jang; Kilb, Werner; Luhmann, Heiko J

    2010-10-01

    The appearance of spontaneous correlated activity is a fundamental feature of developing neuronal networks in vivo and in vitro. To elucidate whether the ontogeny of correlated activity is paralleled by the appearance of specific spike patterns we used a template-matching algorithm to detect repetitive spike patterns in multi-electrode array recordings from cultures of dissociated mouse neocortical neurons between 6 and 15 days in vitro (div). These experiments demonstrated that the number of spiking neurons increased significantly between 6 and 15 div, while a significantly synchronized network activity appeared at 9 div and became the main discharge pattern in the subsequent div. Repetitive spike patterns with a low complexity were first observed at 8 div. The number of repetitive spike patterns in each dataset as well as their complexity and recurrence increased during development in vitro. The number of links between neurons implicated in repetitive spike patterns, as well as their strength, showed a gradual increase during development. About 8% of the spike sequences contributed to more than one repetitive spike patterns and were classified as core patterns. These results demonstrate for the first time that defined neuronal assemblies, as represented by repetitive spike patterns, appear quite early during development in vitro, around the time synchronized network burst become the dominant network pattern. In summary, these findings suggest that dissociated neurons can self-organize into complex neuronal networks that allow reliable flow and processing of neuronal information already during early phases of development.

  8. Repetitive transcranial magnetic stimulation for hallucination in schizophrenia spectrum disorders A meta-analysis***

    Institute of Scientific and Technical Information of China (English)

    Yingli Zhang; Wei Liang; Shichang Yang; Ping Dai; Lijuan Shen; Changhong Wang

    2013-01-01

    OBJECTIVE: This study assessed the efficacy and tolerability of repetitive transcranial magnetic stimulation for treatment of auditory hal ucination of patients with schizophrenia spectrum disorders. DATA SOURCES: Online literature retrieval was conducted using PubMed, ISI Web of Science, EMBASE, Medline and Cochrane Central Register of Control ed Trials databases from January 1985 to May 2012. Key words were “transcranial magnetic stimulation”, “TMS”, “repetitive transcranial magnetic stimulation”, and “hal ucination”. STUDY SELECTION: Selected studies were randomized control ed trials assessing therapeutic ef-ficacy of repetitive transcranial magnetic stimulation for hal ucination in patients with schizophrenia spectrum disorders. Experimental intervention was low-frequency repetitive transcranial magnetic stimulation in left temporoparietal cortex for treatment of auditory hal ucination in schizophrenia spectrum disorders. Control groups received sham stimulation. MAIN OUTCOME MEASURES: The primary outcome was total scores of Auditory Hal ucinations Rating Scale, Auditory Hal ucination Subscale of Psychotic Symptom Rating Scale, Positive and Negative Symptom Scale-Auditory Hal ucination item, and Hal ucination Change Scale. Secondary outcomes included response rate, global mental state, adverse effects and cognitive function. RESULTS: Seventeen studies addressing repetitive transcranial magnetic stimulation for treatment of schizophrenia spectrum disorders were screened, with controls receiving sham stimulation. Al data were completely effective, involving 398 patients. Overal mean weighted effect size for repeti-tive transcranial magnetic stimulation versus sham stimulation was statistical y significant (MD =-0.42, 95%CI: -0.64 to -0.20, P = 0.000 2). Patients receiving repetitive transcranial magnetic stimulation responded more frequently than sham stimulation (OR = 2.94, 95%CI: 1.39 to 6.24, P =0.005). No significant differences were found

  9. The development of a repetition-load scheme for the eccentric-only bench press exercise.

    Science.gov (United States)

    Moir, Gavin L; Erny, Kyle F; Davis, Shala E; Guers, John J; Witmer, Chad A

    2013-01-01

    The purpose of the present study was to develop a repetition-load scheme for the eccentric-only bench press exercise. Nine resistance trained men (age: 21.6 ± 1.0 years; 1-repetition maximum [RM] bench press: 137.7 ± 30.4 kg) attended four testing sessions during a four week period. During the first session each subject's 1-RM bench press load utilizing the stretch-shortening cycle was determined. During the remaining sessions they performed eccentric-only repetitions to failure using supra-maximal loads equivalent to 110%, 120% and 130% of their 1-RM value with a constant cadence (30 reps·min(-1)). Force plates and a three dimensional motion analysis system were used during these final three sessions in order to evaluate kinematic and kinetic variables. More repetitions were completed during the 110% 1-RM condition compared to the 130% 1-RM condition (p=0.01). Mean total work (p=0.046) as well as vertical force (p=0.049), vertical work (p=0.017), and vertical power output (p=0.05) were significantly greater during the 130% 1-RM condition compared to the 110% 1-RM condition. A linear function was fitted to the number of repetitions completed under each load condition that allowed the determination of the maximum number of repetitions that could be completed under other supra-maximal loads. This linear function predicted an eccentric-only 1-RM in the bench press with a load equivalent to 164.8% 1-RM, producing a load of 227.0 ± 50.0 kg. The repetition-load scheme presented here should provide a starting point for researchers to investigate the kinematic, kinetic and metabolic responses to eccentric-only bench press workouts.

  10. Comparing communicative competence in child and chimp: the pragmatics of repetition.

    Science.gov (United States)

    Greenfield, P M; Savage-Rumbaugh, E S

    1993-02-01

    Through an analysis of chimpanzee-human discourse, we show that two Pan troglodytes chimpanzees and two Pan paniscus chimpanzees (bonobos) exposed to a humanly devised symbol system use partial or complete repetition of others' symbols, as children do: they do not produce rote imitations, but instead use repetition to fulfil a variety of pragmatic functions in discourse. These functions include agreement, request, promise, excitement, and selection from alternatives. In so doing, the chimpanzees demonstrate contingent turn-taking and the use of simple devices for lexical cohesion. In short, they demonstrate conversational competence. Because of the presence of this conversational competence in three sibling species, chimpanzees, bonobos, and humans, it is concluded that the potential to express pragmatic functions through repetition was part of the evolutionary history of human language, present in our common ancestor before the phylogenetic divergence of hominids and chimpanzees. In the context of these similarities, two interesting differences appeared: (I) Human children sometimes used repetition to stimulate more talk in their conversational partner; the chimpanzees, in contrast, use repetition exclusively to forward the non-verbal action. This difference may illuminate a unique feature of human linguistic communication, or it may simply reflect a modality difference (visual symbols used by the chimpanzees, speech used by the children) in the symbol systems considered in this research. A second difference seems likely to reflect a true species difference: utterance length. The one- and two-symbol repetitions used by the chimpanzees to fulfil a variety of pragmatic functions were less than half the maximum length found in either the visual symbol combinations addressed to them by their adult human caregivers or the oral repetitions of two-year-old children. This species difference probably reflects the evolution of increased brain size and consequent increased

  11. The Differential Effects of Two Types of Task Repetition on the Complexity, Accuracy, and Fluency in Computer-Mediated L2 Written Production: A Focus on Computer Anxiety

    Science.gov (United States)

    Amiryousefi, Mohammad

    2016-01-01

    Previous task repetition studies have primarily focused on how task repetition characteristics affect the complexity, accuracy, and fluency in L2 oral production with little attention to L2 written production. The main purpose of the study reported in this paper was to examine the effects of task repetition versus procedural repetition on the…

  12. The Differential Effects of Two Types of Task Repetition on the Complexity, Accuracy, and Fluency in Computer-Mediated L2 Written Production: A Focus on Computer Anxiety

    Science.gov (United States)

    Amiryousefi, Mohammad

    2016-01-01

    Previous task repetition studies have primarily focused on how task repetition characteristics affect the complexity, accuracy, and fluency in L2 oral production with little attention to L2 written production. The main purpose of the study reported in this paper was to examine the effects of task repetition versus procedural repetition on the…

  13. Experimental study of polarity dependence in repetitive nanosecond-pulse breakdown

    Institute of Scientific and Technical Information of China (English)

    Shao Tao; Sun Guang-Sheng; Yan Ping; Wang Jue; Yuan Wei-Qun; Zhang Shi-Chang

    2007-01-01

    Pulsed breakdown of dry air at ambient pressure has been investigated in the point-plane geometry,using repetitive nanosecond pulses with 10 ns risetime,20-30 as duration,and up to 100 kV amplitude.A major concern in this paper is to study the dependence of breakdown strength on the point-electrode polarity.Applied voltage,breakdown current and repetitive stressing time are measured under the experimental conditions of some variables including pulse voltage peak,gap spacing and repetition rate.The results show that increasing the E-field strength can decrease breakdown time lag,repetitive stressing time and the number of applied pulses as expected.However,compared with the traditional polarity dependence it is weakened and not significant in the repetitive nanosecond-pulse breakdown.The ambiguous polaxity dependence in the experimental study is involved with an accumulation effect of residual charges and metastable states.Moreover,it is suggested that the reactions associated with the detachment of negative ions and impact deactivation of metastable specms could provide a source of primary initiating electrons for breakdown.

  14. RepPop: a database for repetitive elements in Populus trichocarpa

    Directory of Open Access Journals (Sweden)

    Xu Ying

    2009-01-01

    Full Text Available Abstract Background Populus trichocarpa is the first tree genome to be completed, and its whole genome is currently being assembled. No functional annotation about the repetitive elements in the Populus trichocarpa genome is currently available. Results We predicted 9,623 repetitive elements in the Populus trichocarpa genome, and assigned functions to 3,075 of them (31.95%. The 9,623 repetitive elements cover ~40% of the current (partially assembled genome. Among the 9,623 repetitive elements, 668 have copies only in the contigs that have not been assigned to one of the 19 chromosome while the rest all have copies in the partially assembled chromosomes. Conclusion All the predicted data are organized into an easy-to-use web-browsable database, RepPop. Various search capabilities are provided against the RepPop database. A Wiki system has been set up to facilitate functional annotation and curation of the repetitive elements by a community rather than just the database developer. The database RepPop will facilitate the assembling and functional characterization of the Populus trichocarpa genome.

  15. Long-Term Cognitive and Neuropsychiatric Consequences of Repetitive Concussion and Head-Impact Exposure.

    Science.gov (United States)

    McAllister, Thomas; McCrea, Michael

    2017-03-01

    Initially, interest in sport-related concussion arose from the premise that the study of athletes engaged in sports associated with high rates of concussion could provide insight into the mechanisms, phenomenology, and recovery from mild traumatic brain injury. Over the last decade, concerns have focused on the possibility that, for some athletes, repetitive concussions may raise the long-term risk for cognitive decline, neurobehavioral changes, and neurodegenerative disease. First conceptualized as a discrete event with variable recovery trajectories, concussion is now viewed by some as a trigger of neurobiological events that may influence neurobehavioral function over the course of the life span. Furthermore, advances in technology now permit us to gain a detailed understanding of the frequency and intensity of repetitive head impacts associated with contact sports (eg, football, ice hockey). Helmet-based sensors can be used to characterize the kinematic features of concussive impacts, as well as the profiles of typical head-impact exposures experienced by athletes in routine sport participation. Many large-magnitude impacts are not associated with diagnosed concussions, whereas many diagnosed concussions are associated with more modest impacts. Therefore, a full understanding of this topic requires attention to not only the effects of repetitive concussions but also overall exposure to repetitive head impacts. This article is a review of the current state of the science on the long-term neurocognitive and neurobehavioral effects of repetitive concussion and head-impact exposure in contact sports.

  16. Decreased microvascular cerebral blood flow assessed by diffuse correlation spectroscopy after repetitive concussions in mice.

    Science.gov (United States)

    Buckley, Erin M; Miller, Benjamin F; Golinski, Julianne M; Sadeghian, Homa; McAllister, Lauren M; Vangel, Mark; Ayata, Cenk; Meehan, William P; Franceschini, Maria Angela; Whalen, Michael J

    2015-12-01

    Repetitive concussions are associated with long-term cognitive dysfunction that can be attenuated by increasing the time intervals between concussions; however, biomarkers of the safest rest interval between injuries remain undefined. We hypothesize that deranged cerebral blood flow (CBF) is a candidate biomarker for vulnerability to repetitive concussions. Using a mouse model of human concussion, we examined the effect of single and repetitive concussions on cognition and on an index of CBF (CBFi) measured with diffuse correlation spectroscopy. After a single mild concussion, CBFi was reduced by 35±4% at 4 hours (Pconcussions spaced 1 day apart, CBFi was also reduced from preinjury levels 4 hours after each concussion but had returned to preinjury levels by 72 hours after the final concussion. Interestingly, in this repetitive concussion model, lower CBFi values measured both preinjury and 4 hours after the third concussion were associated with worse performance on the Morris water maze assessed 72 hours after the final concussion. We conclude that low CBFi measured either before or early on in the evolution of injury caused by repetitive concussions could be a useful predictor of cognitive outcome.

  17. Repetition priming of words and nonwords in Alzheimer's disease and normal aging

    Science.gov (United States)

    Ober, Beth A.; Shenaut, Gregory K.

    2014-01-01

    Objective This study examines the magnitude and direction of nonword and word lexical decision repetition priming effects in Alzheimer’s disease (AD) and normal aging, focusing specifically on the negative priming effect sometimes observed with repeated nonwords. Method Probable Alzheimer's disease (AD) patients (30), elderly normal controls (34), and young normal controls (49) participated in a repetition priming experiment using low-frequency words and word-like nonwords with a letter-level orthographic orienting task at study followed by a lexical decision test phase. Results Although participants' reaction times were longer in AD compared to elderly normal, and elderly normal compared to young normal, the repetition priming effect and the degree to which the repetition priming effect was reversed for nonwords compared to words was unaffected by AD or normal aging. Conclusion AD patients, like young and elderly normal participants, are able to modify (in the case of words) and create (in the case of nonwords) long-term memory traces for lexical stimuli, based on a single orthographic processing trial. The nonword repetition results are discussed from the perspective of new vocabulary learning commencing with a provisional lexical memory trace created after orthographic encoding of a novel word-like letter string. PMID:25000325

  18. Unsuppressible Repetition Suppression and exemplar-specific Expectation Suppression in the Fusiform Face Area.

    Science.gov (United States)

    Pajani, Auréliane; Kouider, Sid; Roux, Paul; de Gardelle, Vincent

    2017-12-01

    Recent work casts Repetition Suppression (RS), i.e. the reduced neural response to repeated stimuli, as the consequence of reduced surprise for repeated inputs. This research, along with other studies documenting Expectation Suppression, i.e. reduced responses to expected stimuli, emphasizes the role of expectations and predictive codes in perception. Here, we use fMRI to further characterize the nature of predictive signals in the human brain. Prior to scanning, participants were implicitly exposed to associations within face pairs. Critically, we found that this resulted in exemplar-specific Expectation Suppression in the fusiform face-sensitive area (FFA): individual faces that could be predicted from the associations elicited reduced FFA responses, as compared to unpredictable faces. Thus, predictive signals in the FFA are specific to face exemplars, and not only generic to the category of face stimuli. In addition, we show that under such circumstances, the occurrence of surprising repetitions did not trigger enhanced brain responses, as had been recently hypothesized, but still suppressed responses, suggesting that repetition suppression might be partly 'unsuppressible'. Repetition effects cannot be fully modulated by expectations, which supports the recent view that expectation and repetition effects rest on partially independent mechanisms. Altogether, our study sheds light on the nature of expectation signals along the perceptual system.

  19. Switchable repetition rate bound solitons passively mode-locked fiber laser

    Science.gov (United States)

    Wang, Xuqin; Yao, Yong

    2016-11-01

    We present a kind of a switchable repetition rate mode-locked of bound-state solitons in a fiber laser based on Bi2Se3 saturable absorber (SA). In the fiber laser, two forms of the bound-state optical spectrum with central wavelength of 1532 nm are observed. The fiber laser is operate at the abnormal group velocity dispersion and the bound state pulses are equally distributed to the temporal domain. The fundamental cavity repetition-rate is 1.11 MHz with a pulse duration of 2.27 ps. The output average power and the pulse peak energy are 1.53 mW and 607 W respectively, which the pump power is 267 mW. The different repetition-rates are also achieved by changing the pump power or adjusting the angle of polarization controller. In the experiment, the repetition-rate is switched from 1.11 MHz to 41.32 MHz (37th-order, the highest repetition-rate).

  20. An educational approach to an epidemic of repetitive motion injuries among office workers

    Energy Technology Data Exchange (ETDEWEB)

    Halunen, L.J.

    1988-09-23

    Among office workers, repetitive motion injuries such as tendonitis, muscle fatigue, and nerve irritation (caused by poor posture and arm/hand positioning while performing repetitive tasks) are a fairly new phenomenon. Office workers and their managers are not prepared to respond properly to the identification and treatment of these injuries. We found an unusually high incidence within one department at a large research facility--the Lawrence Livermore National Laboratory--and developed an educational approach to reduce the frequency and severity of these injuries. Our approach was to inform the workers and managers about the origins and severity of repetitive motion injuries and their effect on the work force. Classes in ergonomic adjustment of video workstations were scheduled for all personnel who had jobs that required heavy keyboard use. The individual's responsibility in reporting any symptoms of repetitive motion injury was emphasized. We stressed to management the seriousness of the problem, the desirability of obtaining improved equipment workers may need, or the possibility of arranging a lighter workload for those showing symptoms of repetitive motion injuries. We followed these classes and briefings with additional videotaped material and written guidelines, pamphlets, and articles for further study and discussion. Early results indicate that informed workers in a supportive environment detect symptoms earlier, and therefore recover more quickly; managers who understand the problem and are able to respond positively gain better labor relations as well as lower injury rates. 4 refs., 2 figs.

  1. Low-frequency repetitive transcranial magnetic simulation prevents chronic epileptic seizure*

    Institute of Scientific and Technical Information of China (English)

    Yinxu Wang; Xiaoming Wang; Sha Ke; Juan Tan; Litian Hu; Yaodan Zhang; Wenjuan Cui

    2013-01-01

    Although low-frequency repetitive transcranial magnetic simulation can potentially treat epilepsy, its underlying mechanism remains unclear. This study investigated the influence of low-frequency re-petitive transcranial magnetic simulation on changes in several nonlinear dynamic electroenceph-alographic parameters in rats with chronic epilepsy and explored the mechanism underlying repeti-tive transcranial magnetic simulation-induced antiepileptic effects. An epilepsy model was estab-lished using lithium-pilocarpine intraperitoneal injection into adult Sprague-Dawley rats, which were then treated with repetitive transcranial magnetic simulation for 7 consecutive days. Nonlinear elec-electroencephalographic parameters were obtained from the rats at 7, 14, and 28 days post-stimulation. Results showed significantly lower mean correlation-dimension and Kolmogo-rov-entropy values for stimulated rats than for non-stimulated rats. At 28 days, the complexity and point-wise correlation dimensional values were lower in stimulated rats. Low-frequency repetitive transcranial magnetic simulation has suppressive effects on electrical activity in epileptic rats, thus explaining its effectiveness in treating epilepsy.

  2. Words translated in sentence contexts produce repetition priming in visual word comprehension and spoken word production.

    Science.gov (United States)

    Francis, Wendy S; Camacho, Alejandra; Lara, Carolina

    2014-10-01

    Previous research with words read in context at encoding showed little if any long-term repetition priming. In Experiment 1, 96 Spanish-English bilinguals translated words in isolation or in sentence contexts at encoding. At test, they translated words or named pictures corresponding to words produced at encoding and control words not previously presented. Repetition priming was reliable in all conditions, but priming effects were generally smaller for contextualized than for isolated words. Repetition priming in picture naming indicated priming from production in context. A componential analysis indicated priming from comprehension in context, but only in the less fluent language. Experiment 2 was a replication of Experiment 1 with auditory presentation of the words and sentences to be translated. Repetition priming was reliable in all conditions, but priming effects were again smaller for contextualized than for isolated words. Priming in picture naming indicated priming from production in context, but the componential analysis indicated no detectable priming for auditory comprehension. The results of the two experiments taken together suggest that repetition priming reflects the long-term learning that occurs with comprehension and production exposures to words in the context of natural language.

  3. Articulation-based sound perception in verbal repetition: A functional NIRS study

    Directory of Open Access Journals (Sweden)

    Sejin eYoo

    2013-09-01

    Full Text Available Verbal repetition is a fundamental language capacity where listening and speaking are inextricably coupled with each other. We have recently reported that the left inferior frontal gyrus (IFG harbors articulation-based codes, as evidenced by activation during repetition of meaningless speech sounds, i.e., pseudowords. In this study, we aimed at confirming this finding and further investigating the possibility that sound perception as well as articulation is subserved by neural circuits in this region. Using functional near-infrared spectroscopy (fNIRS, we monitored changes of hemoglobin (Hb concentration at IFG bilaterally, while subjects verbally repeated pseudowords and words. The results revealed that the proportion of oxygenated hemoglobin (O2Hb over total Hb was significantly higher at the left IFG during repetition of pseudowords than that of words, replicating the observation by functional MRI and indicating that the region processes articulatory codes for verbal repetition. More importantly for this study, hemodynamic modulations were observed at both IFG during passive listening without repetition to various sounds, including natural environmental sounds, animal vocalizations, and human nonspeech sounds. Furthermore, the O2Hb concentration increased at the left IFG but decreased at the right IFG for both speech and non-speech sounds. These findings suggest that both speech and non-speech sounds may be processed and maintained by a neural mechanism for sensorimotor integration using articulatory codes at the left IFG.

  4. Relationships Between Refraining From Catastrophic Thinking, Repetitive Negative Thinking, and Psychological Distress.

    Science.gov (United States)

    Sugiura, Tomoko; Sugiura, Yoshinori

    2016-10-01

    Skills to refrain from catastrophic thinking were negatively related to worry and a wide range of psychological distress. Repetitive negative thinking (including worry) is proposed as a common etiological factor for a wide range of psychological distress. Therefore, reduced repetitive negative thinking would mediate the negative relation between refraining from catastrophic thinking and psychological distress (depression, social anxiety, phobia, generalized anxiety, and obsessions and compulsions). As an overlap between five indices of psychological distress was expected, we first computed latent factors underlying them, which were then predicted by refraining from catastrophic thinking and repetitive negative thinking. Cross-sectional questionnaire data from 125 nonclinical voluntarily participating students (M age = 19.0 years, SD = 3.6; 54% women) supported the predictions: refraining from catastrophic thinking was negatively correlated with depression, social anxiety, phobia, generalized anxiety, and obsession and compulsion. Repetitive negative thinking mediated the negative relationship between refraining from catastrophic thinking and latent factors underlying psychological distress (Fear and Distress). Refraining from catastrophic thinking may be negatively correlated with psychological distress due to its negative relation to repetitive negative thinking.

  5. The Organization of Repetitive DNA in the Genomes of Amazonian Lizard Species in the Family Teiidae.

    Science.gov (United States)

    Carvalho, Natalia D M; Pinheiro, Vanessa S S; Carmo, Edson J; Goll, Leonardo G; Schneider, Carlos H; Gross, Maria C

    2015-01-01

    Repetitive DNA is the largest fraction of the eukaryote genome and comprises tandem and dispersed sequences. It presents variations in relation to its composition, number of copies, distribution, dynamics, and genome organization, and participates in the evolutionary diversification of different vertebrate species. Repetitive sequences are usually located in the heterochromatin of centromeric and telomeric regions of chromosomes, contributing to chromosomal structures. Therefore, the aim of this study was to physically map repetitive DNA sequences (5S rDNA, telomeric sequences, tropomyosin gene 1, and retroelements Rex1 and SINE) of mitotic chromosomes of Amazonian species of teiids (Ameiva ameiva, Cnemidophorus sp. 1, Kentropyx calcarata, Kentropyx pelviceps, and Tupinambis teguixin) to understand their genome organization and karyotype evolution. The mapping of repetitive sequences revealed a distinct pattern in Cnemidophorus sp. 1, whereas the other species showed all sequences interspersed in the heterochromatic region. Physical mapping of the tropomyosin 1 gene was performed for the first time in lizards and showed that in addition to being functional, this gene has a structural function similar to the mapped repetitive elements as it is located preferentially in centromeric regions and termini of chromosomes.

  6. Sources of Phoneme Errors in Repetition: Perseverative, Neologistic, and Lesion Patterns in Jargon Aphasia

    Directory of Open Access Journals (Sweden)

    Emma Pilkington

    2017-05-01

    Full Text Available This study examined patterns of neologistic and perseverative errors during word repetition in fluent Jargon aphasia. The principal hypotheses accounting for Jargon production indicate that poor activation of a target stimulus leads to weakly activated target phoneme segments, which are outcompeted at the phonological encoding level. Voxel-lesion symptom mapping studies of word repetition errors suggest a breakdown in the translation from auditory-phonological analysis to motor activation. Behavioral analyses of repetition data were used to analyse the target relatedness (Phonological Overlap Index: POI of neologistic errors and patterns of perseveration in 25 individuals with Jargon aphasia. Lesion-symptom analyses explored the relationship between neurological damage and jargon repetition in a group of 38 aphasia participants. Behavioral results showed that neologisms produced by 23 jargon individuals contained greater degrees of target lexico-phonological information than predicted by chance and that neologistic and perseverative production were closely associated. A significant relationship between jargon production and lesions to temporoparietal regions was identified. Region of interest regression analyses suggested that damage to the posterior superior temporal gyrus and superior temporal sulcus in combination was best predictive of a Jargon aphasia profile. Taken together, these results suggest that poor phonological encoding, secondary to impairment in sensory-motor integration, alongside impairments in self-monitoring result in jargon repetition. Insights for clinical management and future directions are discussed.

  7. Repetitive transcranial magnetic stimulation improves consciousness disturbance in stroke patients A quantitative electroencephalography spectral power analysis

    Institute of Scientific and Technical Information of China (English)

    Ying Xie; Tong Zhang

    2012-01-01

    Repetitive transcranial magnetic stimulation is a noninvasive treatment technique that can directly alter cortical excitability and improve cerebral functional activity in unconscious patients. To investigate the effects and the electrophysiological changes of repetitive transcranial magnetic stimulation cortical treatment, 10 stroke patients with non-severe brainstem lesions and with disturbance of consciousness were treated with repetitive transcranial magnetic stimulation. A quantitative electroencephalography spectral power analysis was also performed. The absolute power in the alpha band was increased immediately after the first repetitive transcranial magnetic stimulation treatment, and the energy was reduced in the delta band. The alpha band relative power values slightly decreased at 1 day post-treatment, then increased and reached a stable level at 2 weeks post-treatment. Glasgow Coma Score and JFK Coma Recovery Scale-Revised score were improved. Relative power value in the alpha band was positively related to Glasgow Coma Score and JFK Coma Recovery Scale-Revised score. These data suggest that repetitive transcranial magnetic stimulation is a noninvasive, safe, and effective treatment technology for improving brain functional activity and promoting awakening in unconscious stroke patients.

  8. Effects of inspiratory muscle training upon recovery time during high intensity, repetitive sprint activity.

    Science.gov (United States)

    Romer, L M; McConnell, A K; Jones, D A

    2002-07-01

    The present study examined the influence of specific inspiratory muscle training (IMT) upon recovery time during repetitive sprint activity, as well as the physiological and perceptual responses to fixed intensity shuttle running. Using a double-blind placebo-controlled design, 24 male repetitive sprint athletes were assigned randomly to either an IMT (n = 12) or placebo (n = 12) group. The self-selected recovery time during a repetitive sprint test and the physiological response to submaximal endurance exercise were determined. Following completion of baseline and pre-intervention measures, the IMT group performed 30 inspiratory efforts twice daily against a resistance equivalent to 50 % maximum inspiratory mouth pressure (MIP) for 6 wk. The placebo group performed 60 breaths once daily, for 6 wk, at a resistance equivalent to 15 % MIP, a load known to elicit negligible changes in respiratory muscle function. The IMT group improved total recovery time during the repetitive sprint test by 6.2 +/- 1.1 % (mean +/- SEM) above the changes noted for the placebo group (p = 0.006). Blood lactate and perceptual responses to submaximal exercise were also significantly attenuated following IMT (p attenuates the blood lactate and perceptual responses to submaximal endurance exercise. In addition, the present study provides new evidence that IMT improves recovery time during high intensity, intermittent exercise in repetitive sprint athletes.

  9. 德勒兹、莫奈与重复%Deleuze, Monet, and Being Repetitive

    Institute of Scientific and Technical Information of China (English)

    张正平(著)[美; 金浪(译)

    2015-01-01

    Repetition repeats the unrepeatable.Since what is unrepeatable is singular, repetition repeats singularity.This es-say investigates the concept of repetition as articulated by Gilles Deleuze in his Difference and Repetition.Drawing on the principle of seriality governing some of Monet′s paintings, it demonstrates how and to what extent repetition developed by Deleuze parallels Derrida′s idea of differance and moves poststructuralist thinking in a different direction than that guided by phenomenology.%重复是对不可重复之物的重复。既然不可重复之物是独异的,重复也就是对于独异性之重复。通过尝试考察吉尔·德勒兹在其《差异与重复》一书中提出的重复概念,对于主导莫奈绘画的系列原则所进行的勾勒,证明了重复如何以及在何种程度上为德勒兹及德里达的差异概念所发展,并使后结构主义思想转向了不同于现象学主导下的另外方向。

  10. Validation of the French version of a questionnaire that evaluates constructive and non-constructive repetitive thoughts

    OpenAIRE

    Douilliez, Céline; Heeren, Alexandre; Lefèvre, Nathalie; Watkins, Edward; Barnard, Philip; Philippot, Pierre

    2014-01-01

    This article presents the adaptation and the validation of a short self-report questionnaire assessing repetitive thinking, the Mini Cambridge-Exeter Repetitive Thought Scale (Mini-CERTS). This 16 item scale evaluates two dimensions of repetitive thinking: "concrete, experiential thinking" (CET) and "abstract, analytical thinking" (AAT) that may have constructive and unconstructive consequences. A large sample of adult volunteers (n = 247) filled in the Mini-CERTS. Subsamples also responded t...

  11. The role of reminding in the effects of spaced repetitions on cued recall: sufficient but not necessary.

    Science.gov (United States)

    Wahlheim, Christopher N; Maddox, Geoffrey B; Jacoby, Larry L

    2014-01-01

    Three experiments examined the role of study-phase retrieval (reminding) in the effects of spaced repetitions on cued recall. Remindings were brought under task control to evaluate their effects. Participants studied 2 lists of word pairs containing 3 item types: single items that appeared once in List 2, within-list repetitions that appeared twice in List 2, and between-list repetitions that appeared once in List 1 and once in List 2. Our primary interest was in performance on between-list repetitions. Detection of between-list repetitions was encouraged in an n-back condition by instructing participants to indicate when a presented item was a repetition of any preceding item, including items presented in List 1. In contrast, detection of between-list repetitions was discouraged in a within-list back condition by instructing participants only to indicate repetitions occurring in List 2. Cued recall of between-list repetitions was enhanced when instructions encouraged detection of List 1 presentations. These results accord with those from prior experiments showing a role of study-phase retrieval in effects of spacing repetitions. Past experiments have relied on conditionalized data to draw conclusions, producing the possibility that performance benefits merely reflected effects of item selection. By bringing effects under task control, we avoided that problem. Our results provide evidence that reminding resulting from retrieval of earlier presentations plays a role in the effects of spaced repetitions on cued recall. However, our results also reveal that such retrievals are not necessary to produce an effect of spacing repetitions.

  12. Influence of the Repetitive Corrugation on the Mechanism Occuring During Plastic Deformation of CuSn6 Alloy

    OpenAIRE

    Nuckowski P. M.; Kwaśny W.; Rdzawski Z.; Głuchowski W.; Pawlyta M.

    2016-01-01

    This paper presents the research results of CuSn6 alloy strip at semi-hard state, plastically deformed in the process of repetitive corrugation. The influence of process parameters on the mechanical properties and structure of examined alloy were investigated. Examination in high-resolution transmission electron microscopy (HRTEM) confirmed the impact of the repetitive corrugation to obtain the nano-scale structures. It has been found, that the application of repetitive corrugation increases ...

  13. Selective attention modulates visual and haptic repetition priming: effects in aging and Alzheimer's disease.

    Science.gov (United States)

    Ballesteros, Soledad; Reales, José M; Mayas, Julia; Heller, Morton A

    2008-08-01

    In two experiments, we examined the effect of selective attention at encoding on repetition priming in normal aging and Alzheimer's disease (AD) patients for objects presented visually (experiment 1) or haptically (experiment 2). We used a repetition priming paradigm combined with a selective attention procedure at encoding. Reliable priming was found for both young adults and healthy older participants for visually presented pictures (experiment 1) as well as for haptically presented objects (experiment 2). However, this was only found for attended and not for unattended stimuli. The results suggest that independently of the perceptual modality, repetition priming requires attention at encoding and that perceptual facilitation is maintained in normal aging. However, AD patients did not show priming for attended stimuli, or for unattended visual or haptic objects. These findings suggest an early deficit of selective attention in AD. Results are discussed from a cognitive neuroscience approach.

  14. The Response of the Shoulder Complex to Repetitive Work: Implications for Workplace Design.

    Science.gov (United States)

    McDonald, Alison C; Keir, Peter J

    2015-01-01

    The shoulder complex has multiple degrees of freedom and muscular geometry that make it possible to complete tasks with many different kinematic and muscular strategies. Substantial research has investigated the effects of workplace factors (posture and task design) on the shoulder complex. The interactive relationships between workplace factors, however, make it challenging to synthesize the literature to make decisive conclusions regarding the impact of repetitive work. This review summarizes a broad selection of the literature examining the effects of repetitive work on the shoulder complex with respect to kinematic and muscular adaptation strategies to maintain task performance with muscular fatigue. The implications of repetitive work and workplace design on the shoulder complex are discussed.

  15. Near- infrared, mode-locked waveguide lasers with multi-GHz repetition rates

    Science.gov (United States)

    Choudhary, A.; Lagatsky, A. A.; Zhang, Z. Y.; Zhou, K. J.; Wang, Q.; Hogg, R. A.; Pradeesh, K.; Rafailov, E. U.; Resan, B.; Oehler, A. E. H.; Weingarten, K. J.; Sibbett, W.; Brown, C. T. A.; Shepherd, D. P.

    2014-02-01

    In this work, we discuss mode-locking results obtained with low-loss, ion-exchanged waveguide lasers. With Yb3+-doped phosphate glass waveguide lasers, a repetition rate of up to 15.2 GHz was achieved at a wavelength of 1047 nm with an average power of 27 mW and pulse duration of 811 fs. The gap between the waveguide and the SESAM introduced negative group velocity dispersion via the Gires Tournois Interferometer (GTI) effect which allowed the soliton mode-locking of the device. A novel quantum dot SESAM was used to mode-lock Er3+, Yb3+-doped phosphate glass waveguide lasers around 1500 nm. Picosecond pulses were achieved at a maximum repetition rate of 6.8 GHz and an average output power of 30 mW. The repetition rate was tuned by more than 1 MHz by varying the pump power.

  16. Relationship Between Subtypes of Restricted and Repetitive Behaviors and Sleep Disturbance in Autism Spectrum Disorder.

    Science.gov (United States)

    Hundley, Rachel J; Shui, Amy; Malow, Beth A

    2016-11-01

    We examined the association of two types of restricted and repetitive behaviors, repetitive sensory motor (RSM) and insistence on sameness (IS), with sleep problems in children with autism spectrum disorder (ASD). Participants included 532 children (aged 2-17) who participated in the Autism Speaks Autism Treatment Network research registry. Confirmatory factor analysis of the Autism Diagnostic Interview-Revised detected the presence of RSM and IS. RSM behaviors were positively associated with parent-reported sleep problems, and this relationship remained significant after controlling for anxiety symptoms. IS was not significantly associated with sleep problems. Better understanding of the relationship between specific types of repetitive behaviors and sleep problems may allow providers to tailor interventions to the individual presentations of their patients with ASD.

  17. Risk of shoulder tendinitis in relation to shoulder loads in monotonous repetitive work

    DEFF Research Database (Denmark)

    Frost, P.; Bonde, J. P.; Mikkelsen, S.

    2002-01-01

    BACKGROUND: Few studies relate the occurrence of shoulder disorders to quantified ergonomic exposures. This study evaluates the hypothesis that shoulder loads in repetitive work might contribute to the occurrence of shoulder tendinitis. METHODS: This is a cross-sectional study of 1961 workers...... in repetitive work and 782 referents. Shoulder loads were quantified at task level and measures of exposures were assigned based on task distribution. Symptoms in combination with clinical criteria defined shoulder tendinitis. RESULTS: The prevalence of shoulder tendinitis was higher among exposed workers...... risk slightly (OR 1.6, 95% CI 1.0-2.6 per unit). CONCLUSIONS: The results indicate that workers with repetitive tasks have increased risk of shoulder tendinitis, which partially can be attributed to force requirements...

  18. Number of repetitions required to retain single-digit multiplication math facts for elementary students.

    Science.gov (United States)

    Burns, Matthew K; Ysseldyke, Jim; Nelson, Peter M; Kanive, Rebecca

    2015-09-01

    Computational fluency is an important aspect of math proficiency. Despite widely held beliefs about the differential difficulty of single-digit multiplication math facts, little empirical work has examined this issue. The current study analyzed the number of repetitions needed to master multiplication math facts. Data from 15,402 3rd, 4th, and 5th graders were analyzed using a national database. Results suggested that (a) students with lower math skills required significantly (p < .001) more repetitions than more skilled students; (b) across all students, single-digit multiplication facts with 4s, 5s, 6s, and 7s required significantly (p < .001) more repetition than did 2s and 3s; and (c) the number of practice sessions needed to attain mastery significantly (p < .001) decreased with increase in grade level. Implications for instructional planning and implementation are discussed. (c) 2015 APA, all rights reserved).

  19. Basis Function Repetitive And Feedback Control With Application To A Particle Accelerator

    CERN Document Server

    Akogyeram, R A

    2002-01-01

    The thesis addresses three problem areas within repetitive control. Firstly, it addresses issues concerning the ability of repetitive control and feedback control systems to eliminate periodic disturbances occurring above the Nyquist frequency of the hardware. Methods are developed for decomposing and unfolding notch filter or comb filter feedback control so that disturbances above Nyquist frequency can be canceled. Phenomena affecting final error levels are discussed, including error in unfolding, coarseness of zero-order hold cancellation, and waterbed effects in the feedback control system frequency response for different sample rates. Secondly, matched basis function repetitive control laws are developed for batch mode and real time implementation to converge to zero tracking error in the presence of periodic disturbances. For both control methods, conditions are given that guarantee asymptotic and monotonic convergence. Stability tests are formulated to examine stability when the period of a disturbance ...

  20. Polymerase Chain Reaction-based Suppression of Repetitive Sequences in Whole Chromosome Painting Probes for FISH

    Energy Technology Data Exchange (ETDEWEB)

    Dugan, L C; Pattee, M; Williams, J; Eklund, M; Bedford, J S; Christian, A T

    2004-04-21

    We have developed a method to suppress the PCR amplification of repetitive sequences in whole chromosome painting probes by adding Cot-1 DNA to the amplification mixture. The repetitive sequences in the Cot-1 DNA bind to their homologous sequences in the probe library, prevent the binding of primers, and interfere with extension of the probe sequences, greatly decreasing PCR efficiency selectively across these blocked regions. A second labeling reaction is then done and this product is resuspended in FISH hybridization mixture without further addition of blocking DNA. The hybridization produces little if any non-specific binding on any other chromosomes. We have been able to successfully use this procedure with both human and rat chromosome probes. This technique should be applicable in producing probes for CGH, M-FISH and SKY, as well as reducing the presence of repetitive DNA in genomic libraries.

  1. Design of a low emittance and high repetition rate S-band photoinjector

    Science.gov (United States)

    Han, Jang-Hui

    2014-09-01

    As an electron beam injector of X-ray free-electron lasers (FELs), photoinjectors have been developed for the past few decades. Such an injector starting with a photocathode RF gun provides high brightness beams and therefore it is being adopted as an injector of X-ray FELs. In this paper we show how to improve photoinjector performance in terms of emittance and repetition rates by means of injector components optimization, especially with the gun. Transverse emittance at the end of an injector is reduced by optimizing the gun design, gun solenoid position, and accelerating section position. The repetition rate of an injector mainly depends on the gun. It is discussed that a repetition rate of 1 kHz at a normal-conducting S-band photoinjector is feasible by adopting a coaxial RF coupler and improving cooling-water channels surrounding the gun.

  2. Investigating the work-family conflict and health link: Repetitive thought as a mechanism.

    Science.gov (United States)

    Davis, Kelly D; Gere, Judith; Sliwinski, Martin J

    2016-10-06

    Research is needed to investigate mechanisms linking work-family conflict to poor health in working adults. We took a novel approach to build on extant studies by testing a potential mechanism in these associations - repetitive thought. Data came from a sample of 203 partnered working adults. There were significant direct effects of work-family conflict with lower life satisfaction, positive affect, and perceived health as well as greater fatigue. As for total effects, work-family conflict was significantly associated with all health outcomes - life satisfaction, positive affect, negative affect, fatigue, perceived health, and chronic health conditions - in the expected directions through repetitive thought. This study provides support that repetitive thought is one potential mechanism of how work-family conflict can take a toll on psychological and physical health. Findings are discussed in relation to improving workplace policies to improve the health of working adults managing work-family conflict.

  3. Optimizing drive parameters of a nanosecond, repetitively pulsed microdischarge high power 121.6 nm source

    Science.gov (United States)

    Stephens, J.; Fierro, A.; Trienekens, D.; Dickens, J.; Neuber, A.

    2015-02-01

    Utilizing nanosecond high voltage pulses to drive microdischarges (MDs) at repetition rates in the vicinity of 1 MHz previously enabled increased time-averaged power deposition, peak vacuum ultraviolet (VUV) power yield, as well as time-averaged VUV power yield. Here, various pulse widths (30-250 ns), and pulse repetition rates (100 kHz-5 MHz) are utilized, and the resulting VUV yield is reported. It was observed that the use of a 50 ns pulse width, at a repetition rate of 100 kHz, provided 62 W peak VUV power and 310 mW time-averaged VUV power, with a time-averaged VUV generation efficiency of ˜1.1%. Optimization of the driving parameters resulted in 1-2 orders of magnitude increase in peak and time-averaged power when compared to low power, dc-driven MDs.

  4. A vacuum-sealed, gigawatt-class, repetitively pulsed high-power microwave source

    Science.gov (United States)

    Xun, Tao; Fan, Yu-wei; Yang, Han-wu; Zhang, Zi-cheng; Chen, Dong-qun; Zhang, Jian-de

    2017-06-01

    A compact L-band sealed-tube magnetically insulated transmission line oscillator (MILO) has been developed that does not require bulky external vacuum pump for repetitive operations. This device with a ceramic insulated vacuum interface, a carbon fiber array cathode, and non-evaporable getters has a base vacuum pressure in the low 10-6 Pa range. A dynamic 3-D Monte-Carlo model for the molecular flow movement and collision was setup for the MILO chamber. The pulse desorption, gas evolution, and pressure distribution were exactly simulated. In the 5 Hz repetition rate experiments, using a 600 kV diode voltage and 48 kA beam current, the average radiated microwave power for 25 shots is about 3.4 GW in 45 ns pulse duration. The maximum equilibrium pressure is below 4.0 × 10-2 Pa, and no pulse shortening limitations are observed during the repetitive test in the sealed-tube condition.

  5. Surface damage characteristics of CFC and tungsten with repetitive ELM-like pulsed plasma irradiation

    Science.gov (United States)

    Kikuchi, Y.; Nishijima, D.; Nakatsuka, M.; Ando, K.; Higashi, T.; Ueno, Y.; Ishihara, M.; Shoda, K.; Nagata, M.; Kawai, T.; Ueda, Y.; Fukumoto, N.; Doerner, R. P.

    2011-08-01

    Surface damage of carbon fiber composite (CFC) and tungsten (W) due to repetitive ELM-like pulsed plasma irradiation has been investigated by using a magnetized coaxial plasma gun. CX2002U CFC and stress-relieved W samples were exposed to repetitive pulsed deuterium plasmas with duration of ˜0.5 ms, incident ion energy of ˜30 eV, and surface absorbed energy density of ˜0.3-0.7 MJ/m2. Bright spots on a CFC surface during pulsed plasma exposures were clearly observed with a high-speed camera, indicating a local surface heating. No melting of a W surface was observed under a single plasma pulse exposure at energy density of ˜0.7 MJ/m2, although cracks were formed. Cracking of the W surface grew with repetitive pulsed plasma exposures. Subsequently, the surface melted due to localized heat absorption.

  6. Single Longitudinal Mode, High Repetition Rate, Q-switched Ho:YLF Laser for Remote Sensing

    Science.gov (United States)

    Bai, Yingxin; Yu, Jirong; Petzar, Paul; Petros, M.; Chen, Songsheng; Trieu, Bo; Lee, Nyung; Singh, U.

    2009-01-01

    Ho:YLF/LuLiF lasers have specific applications for remote sensing such as wind-speed measurement and carbon dioxide (CO2) concentration measurement in the atmosphere because the operating wavelength (around 2 m) is located in the eye-safe range and can be tuned to the characteristic lines of CO2 absorption and there is strong backward scattering signal from aerosol (Mie scattering). Experimentally, a diode pumped Ho:Tm:YLF laser has been successfully used as the transmitter of coherent differential absorption lidar for the measurement of with a repetition rate of 5 Hz and pulse energy of 75 mJ [1]. For highly precise CO2 measurements with coherent detection technique, a laser with high repetition rate is required to averaging out the speckle effect [2]. In addition, laser efficiency is critically important for the air/space borne lidar applications, because of the limited power supply. A diode pumped Ho:Tm:YLF laser is difficult to efficiently operate in high repetition rate due to the large heat loading and up-conversion. However, a Tm:fiber laser pumped Ho:YLF laser with low heat loading can be operated at high repetition rates efficiently [3]. No matter whether wind-speed or carbon dioxide (CO2) concentration measurement is the goal, a Ho:YLF/LuLiF laser as the transmitter should operate in a single longitudinal mode. Injection seeding is a valid technique for a Q-switched laser to obtain single longitudinal mode operation. In this paper, we will report the new results for a single longitudinal mode, high repetition rate, Q-switched Ho:YLF laser. In order to avoid spectral hole burning and make injection seeding easier, a four mirror ring cavity is designed for single longitudinal mode, high repetition rate Q-switched Ho:YLF laser. The ramp-fire technique is chosen for injection seeding.

  7. Reversal learning in C58 mice: Modeling higher order repetitive behavior.

    Science.gov (United States)

    Whitehouse, Cristina M; Curry-Pochy, Lisa S; Shafer, Robin; Rudy, Joseph; Lewis, Mark H

    2017-08-14

    Restricted, repetitive behaviors are diagnostic for autism and prevalent in other neurodevelopmental disorders. These behaviors cluster as repetitive sensory-motor behaviors and behaviors reflecting resistance to change. The C58 mouse strain is a promising model for these behaviors as it emits high rates of aberrant repetitive sensory-motor behaviors. The purpose of the present study was to extend characterization of the C58 model to resistance to change. This was done by comparing C58 to C57BL/6 mice on a reversal learning task under either a 100% or 80%/20% probabilistic reinforcement schedule. In addition, the effect of environmental enrichment on performance of this task was assessed as this rearing condition markedly reduces repetitive sensory-motor behavior in C58 mice. Little difference was observed between C58 and control mice under a 100% schedule of reinforcement. The 80%/20% probabilistic schedule of reinforcement generated substantial strain differences, however. Importantly, no strain difference was observed in acquisition, but C58 mice were markedly impaired in their ability to reverse their pattern of responding from the previously high density reinforcement side. Environmental enrichment did not impact acquisition under the probabilistic reinforcement schedule, but enriched C58 mice performed significantly better than standard housed C58 mice in reversal learning. Thus, C58 mice exhibit behaviors that reflect both repetitive sensory motor behaviors as well as behavior that reflects resistance to change. Moreover, both clusters of repetitive behavior were attenuated by environmental enrichment. Such findings, along with the reported social deficits in C58 mice, increase the translational value of this mouse model to autism. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. High repetition rate passively Q-switched fiber and microchip lasers for optical resolution photoacoustic imaging

    Science.gov (United States)

    Shi, Wei; Utkin, Ilya; Ranasinghesagara, Janaka; Pan, Lei; Godwal, Yogesh; Kerr, Shaun; Zemp, Roger J.; Fedosejevs, Robert

    2010-02-01

    Optical-resolution photoacoustic microscopy is a novel imaging technology for visualizing optically-absorbing superficial structures in vivo with lateral spatial resolution determined by optical focusing rather than acoustic detection. Since scanning of the illumination spot is required, the imaging speed is limited by the scanning speed and the laser pulse repetition rate. Unfortunately, lasers with high-repetition rate and suitable pulse durations and energies are difficult to find. We are developing compact laser sources for this application. Passively Q-switched fiber and microchip lasers with pulse repetition rates up to 300 kHz are demonstrated. Using a diode-pumped microchip laser fiber-coupled to a large mode-area Yb-doped fiber amplifier we obtained 60μJ 1-ns pulses at the frequency-doubled 532-nm wavelength. The pulse-repetition rate was determined by the power of the microchip laser pump source at 808nm and may exceed 10 kHz. Additionally, a passively Q-switched fiber laser utilizing a Yb-doped double-cladding fiber and an external saturable absorber has shown to produce 250ns pulses at repetition rates of 100-300 KHz. A photoacoustic probe enabling flexible scanning of the focused output of these lasers consisted of a 45-degree glass prism in an optical index-matching fluid. Photoacoustic signals exiting the sample are deflected by the prism to an ultrasound transducer. Phantom studies with a 7.5-micron carbon fiber demonstrate the ability to image with optical rather than acoustic resolution. We believe that the high pulse-repetition rates and the potentially compact and fiber-coupled nature of these lasers will prove important for clinical imaging applications where realtime imaging performance is essential.

  9. Oxotremorine treatment reduces repetitive behaviors in BTBR T+ tf/J mice

    Directory of Open Access Journals (Sweden)

    Dionisio A. Amodeo

    2014-08-01

    Full Text Available Repetitive behaviors with restricted interests is one of the core criteria for the diagnosis of autism spectrum disorder (ASD. Current pharmacotherapies that target the dopaminergic or serotonergic systems have limited effectiveness in treating repetitive behaviors. Previous research has demonstrated that administration of muscarinic cholinergic receptor (mAChR antagonists can exacerbate motor stereotypies while mAChR agonists reduce stereotypies. The present study determined whether the mAChR agonist, oxotremorine affected repetitive behaviors in the BTBR T+ tf/J (BTBR mouse model of autism. To test the effects of oxotremorine on repetitive behaviors, marble burying and grooming behavior were measured in BTBR mice and compared to that in C57BL/6J (B6 mice. The effects of oxotremorine on locomotor activity was also measured. Thirty minutes before each test, mice received an intraperitoneal injection of saline, 0.001 mg or 0.01 mg of oxotremorine methiodide. Saline- treated BTBR mice exhibited increased marble burying and self-grooming behavior compared to that of saline-treated B6 mice. Oxotremorine significantly reduced marble burying and self-grooming behavior in BTBR mice, but had no significant effect in B6 mice. In addition, oxotremorine did not affect locomotor activity in BTBR mice, but significantly reduced locomotor activity in B6 mice at the 0.01 mg dose. These findings demonstrate that activation of mAChRs reduces repetitive behavior in the BTBR mouse and suggest that treatment with a mAChR agonist may be effective in reducing repetitive behaviors in ASD.

  10. Frequency and amplitude characteristics of a high-repetition-rate hybrid TEA-CO/sub 2/ laser

    Energy Technology Data Exchange (ETDEWEB)

    Lachambre, J.L.; Lavigne, P.; Verreault, M.; Otis, G.

    1978-02-01

    The envelope and frequency characteristics of the output pulse of a high-repetition-rate hybrid TEA-CO/sub 2/ laser are presented. Both the intrapulse and interpulse laser frequency stability are experimentally determined at repetition rates up to 300 Hz. The recovery of the CW laser signal following the generation of the TEA laser pulse is analyzed theoretically and experimentally. Short term reproducibilities of + or - 2 MHz are observed at a pulse repetition rate of 300 Hz with initial chirp rates of about 1.5 MHz/microsec. Improvements and limits on power and repetition rate are discussed.

  11. Effects of cue frequency and repetition on prospective memory: an ERP investigation.

    Science.gov (United States)

    Wilson, Jennifer; Cutmore, Tim R H; Wang, Ya; Chan, Raymond C K; Shum, David H K

    2013-11-01

    Prospective memory involves the formation and completion of delayed intentions and is essential for independent living. In this study (n = 33), event-related potentials (ERPs) were used to systematically evaluate the effects of PM cue frequency (10% versus 30%) and PM cue repetition (high versus low) on ERP modulations. PM cues elicited prospective positivity and frontal positivity but not N300, perhaps due to the semantic nature of the task. Results of this study revealed an interesting interaction between PM cue frequency and PM cue repetition for prospective positivity and frontal positivity, highlighting the importance of taking both factors into account when designing future studies.

  12. A contactless microwave-based diagnostic tool for high repetition rate laser systems

    CERN Document Server

    Braggio, C

    2014-01-01

    We report on a novel electro-optic device for the diagnostics of high repetition rate laser systems. It is composed of a microwave receiver and of a second order nonlinear crystal, whose irradiation with a train of short laser pulses produces a time-dependent polarization in the crystal itself as a consequence of optical rectification. This process gives rise to the emission of microwave radiation that is detected by a receiver and is analyzed to infer the repetition rate and intensity of the pulses. We believe that this new method may overcome some of the limitations of photodetection techniques.

  13. Outcomes in spasticity after repetitive transcranial magnetic and transcranial direct current stimulations

    Institute of Scientific and Technical Information of China (English)

    Aysegul Gunduz; Hatice Kumru; Alvaro Pascual-Leone

    2014-01-01

    Non-invasive brain stimulations mainly consist of repetitive transcranial magnetic stimulation and transcranial direct current stimulation. Repetitive transcranial magnetic stimulation exhib-its satisfactory outcomes in improving multiple sclerosis, stroke, spinal cord injury and cerebral palsy-induced spasticity. By contrast, transcranial direct current stimulation has only been studied in post-stroke spasticity. To better validate the effcacy of non-invasive brain stimulations in im-proving the spasticity post-stroke, more prospective cohort studies involving large sample sizes are needed.

  14. High-Fidelity Adaptive Qubit Detection through Repetitive Quantum Nondemolition Measurements

    Science.gov (United States)

    Hume, D. B.; Rosenband, T.; Wineland, D. J.

    2007-09-01

    Using two trapped ion species (Al+27 and Be+9) as primary and ancillary quantum systems, we implement qubit measurements based on the repetitive transfer of information and quantum nondemolition detection. The repetition provides a natural mechanism for an adaptive measurement strategy, which leads to exponentially lower error rates compared to using a fixed number of detection cycles. For a single qubit we demonstrate 99.94% measurement fidelity. We also demonstrate a technique for adaptively measuring multiple qubit states using a single ancilla, and apply the technique to spectroscopy of an optical clock transition.

  15. DFB diode seeded low repetition rate fiber laser system operating in burst mode

    Science.gov (United States)

    Šajn, M.; Petelin, J.; Agrež, V.; Vidmar, M.; Petkovšek, R.

    2017-02-01

    A distributed feedback (DFB) diode, gain switched to produce pulses from 60 ps at high peak power of over 0.5 W, is used in burst mode to seed a fiber amplifier chain. High seed power, spectral filtering between amplifier stages and pulsed pumping are used to mitigate amplified spontaneous emission (ASE). The effect of pulse pumping synchronized with the seed on the ASE is explored for the power amplifier at low repetition. Different input and output energies at different burst repetition rates are examined and up to 85% reduction in ASE is achieved compared to continuous pumping. Finally, a numerical model is used to predict further reduction of ASE.

  16. High power, high repetition rate, few picosecond Nd:LuVO₄ oscillator with cavity dumping.

    Science.gov (United States)

    Gao, Peng; Guo, Jie; Li, Jinfeng; Lin, Hua; Yu, Haohai; Zhang, Huaijin; Liang, Xiaoyan

    2015-12-28

    We investigate the potential use of Nd:LuVO4 in high average power, high repetition rate ultrafast lasers. Maximum mode-locked average power of 28 W is obtained at the repetition rate of 58 MHz. The shortest pulse duration is achieved at 4 ps without dispersion compensation. With a cavity dumping technique, the pulse energy is scaling up to 40.7 μJ at 300 kHz and 14.3 μJ at 1.5 MHz.

  17. Low-loss waveguides fabricated in BK7 glass by high repetition rate femtosecond fiber laser.

    Science.gov (United States)

    Eaton, Shane M; Ng, Mi Li; Bonse, Jörn; Mermillod-Blondin, Alexandre; Zhang, Haibin; Rosenfeld, Arkadi; Herman, Peter R

    2008-04-20

    For the first time femtosecond-laser writing has inscribed low-loss optical waveguides in Schott BK7 glass, a commercially important type of borosilicate widely used in optical applications. The use of a variable repetition rate laser enabled the identification of a narrow processing window at 1 MHz repetition rate with optimal waveguides exhibiting propagation losses of 0.3 dB/cm and efficient mode matching to standard optical fibers at a 1550 nm wavelength. The waveguides were characterized by complementary phase contrast and optical transmission microscopy, identifying a micrometer-sized guiding region within a larger complex structure of both positive and negative refractive index variations.

  18. High-q microring resonator with narrow free spectral range for pulse repetition rate multiplication

    DEFF Research Database (Denmark)

    Pu, Minhao; Ji, Hua; Frandsen, Lars Hagedorn

    2009-01-01

    We demonstrate a silicon-on-insulator microring resonator with a free-spectral-range of 0.32 nm, an extinction ratio of 27 dB, and a quality factor of ~140900 at 1550 nm that is used for pulse repetition-rate multiplication from 10 to 40 GHz.......We demonstrate a silicon-on-insulator microring resonator with a free-spectral-range of 0.32 nm, an extinction ratio of 27 dB, and a quality factor of ~140900 at 1550 nm that is used for pulse repetition-rate multiplication from 10 to 40 GHz....

  19. Programmable Control of the Pulse Repetition Rate in the Multiwave Strontium Vapor Laser System

    Directory of Open Access Journals (Sweden)

    Soldatov Anatoly

    2016-01-01

    Full Text Available The aim of the present work was the development of laser systems for ablation of biological tissues with a programmable control over the lasing pulse repetition rate in a wide range. A two-stage laser system consisting of a master oscillator and a power amplifier based on strontium vapor laser has been developed. The operation of the laser system in a single-pulse mode operation, multipulse mode operation, and with a pulse repetition rate up to 20 kHz has been technically implemented. The possibility of a bone tissue ablation with no visible thermal damage is shown.

  20. Dual-Comb Coherent Raman Spectroscopy with Lasers of 1-GHz Pulse Repetition Frequency

    CERN Document Server

    Mohler, Kathrin J; Yan, Ming; Hänsch, Theodor W; Picqué, Nathalie

    2016-01-01

    We extend the technique of multiplex coherent Raman spectroscopy with two femtosecond mode-locked lasers to oscillators of a pulse repetition frequency of 1 GHz. We demonstrate spectra of liquids, which span 1100 cm$^{-1}$ of Raman shifts. At a resolution of 6 cm$^{-1}$, their measurement time may be as short as 5 microseconds for a refresh rate of 2 kHz. The waiting period between acquisitions is improved ten-fold compared to previous experiments with two lasers of 100-MHz repetition frequencies.

  1. Injector Beam Dynamics for a High-Repetition Rate 4th-Generation Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Papadopoulos, C. F.; Corlett, J.; Emma, P.; Filippetto, D.; Penn, G.; Qiang, J.; Reinsch, M.; Sannibale, F.; Steier, C.; Venturini, M.; Wells, R.

    2013-05-20

    We report on the beam dynamics studies and optimization methods for a high repetition rate (1 MHz) photoinjector based on a VHF normal conducting electron source. The simultaneous goals of beamcompression and reservation of 6-dimensional beam brightness have to be achieved in the injector, in order to accommodate a linac driven FEL light source. For this, a parallel, multiobjective optimization algorithm is used. We discuss the relative merits of different injector design points, as well as the constraints imposed on the beam dynamics by technical considerations such as the high repetition rate.

  2. A Device and Methodology for Measuring Repetitive Lifting VO2max (Oxygen Consumption Rate)

    Science.gov (United States)

    1987-08-01

    and its estimate from skinfold thicknesses ; measurements on 481 men and women aged from 16 to 72 years. Br J Nutr 32:77-92. 3. Intaranont K, Ayoub MM...Justificaton --. By ......... AvaI~bty Co’der, L Ust Avdi iUl I r /1- Table of Contents Table of Contents iii List of Figures iv List of Tables v...during 28 repetitive lifting exercise iv List of Tables 1. Repetitive lifting device specifications 15 2. Subject sample descriptive data 24 3

  3. Contrasting the Chromosomal Organization of Repetitive DNAs in Two Gryllidae Crickets with Highly Divergent Karyotypes.

    Science.gov (United States)

    Palacios-Gimenez, Octavio M; Carvalho, Carlos Roberto; Ferrari Soares, Fernanda Aparecida; Cabral-de-Mello, Diogo C

    2015-01-01

    A large percentage of eukaryotic genomes consist of repetitive DNA that plays an important role in the organization, size and evolution. In the case of crickets, chromosomal variability has been found using classical cytogenetics, but almost no information concerning the organization of their repetitive DNAs is available. To better understand the chromosomal organization and diversification of repetitive DNAs in crickets, we studied the chromosomes of two Gryllidae species with highly divergent karyotypes, i.e., 2n(♂) = 29,X0 (Gryllus assimilis) and 2n = 9, neo-X1X2Y (Eneoptera surinamensis). The analyses were performed using classical cytogenetic techniques, repetitive DNA mapping and genome-size estimation. Conserved characteristics were observed, such as the occurrence of a small number of clusters of rDNAs and U snDNAs, in contrast to the multiple clusters/dispersal of the H3 histone genes. The positions of U2 snDNA and 18S rDNA are also conserved, being intermingled within the largest autosome. The distribution and base-pair composition of the heterochromatin and repetitive DNA pools of these organisms differed, suggesting reorganization. Although the microsatellite arrays had a similar distribution pattern, being dispersed along entire chromosomes, as has been observed in some grasshopper species, a band-like pattern was also observed in the E. surinamensis chromosomes, putatively due to their amplification and clustering. In addition to these differences, the genome of E. surinamensis is approximately 2.5 times larger than that of G. assimilis, which we hypothesize is due to the amplification of repetitive DNAs. Finally, we discuss the possible involvement of repetitive DNAs in the differentiation of the neo-sex chromosomes of E. surinamensis, as has been reported in other eukaryotic groups. This study provided an opportunity to explore the evolutionary dynamics of repetitive DNAs in two non-model species and will contribute to the understanding of

  4. Contrasting the Chromosomal Organization of Repetitive DNAs in Two Gryllidae Crickets with Highly Divergent Karyotypes.

    Directory of Open Access Journals (Sweden)

    Octavio M Palacios-Gimenez

    Full Text Available A large percentage of eukaryotic genomes consist of repetitive DNA that plays an important role in the organization, size and evolution. In the case of crickets, chromosomal variability has been found using classical cytogenetics, but almost no information concerning the organization of their repetitive DNAs is available. To better understand the chromosomal organization and diversification of repetitive DNAs in crickets, we studied the chromosomes of two Gryllidae species with highly divergent karyotypes, i.e., 2n(♂ = 29,X0 (Gryllus assimilis and 2n = 9, neo-X1X2Y (Eneoptera surinamensis. The analyses were performed using classical cytogenetic techniques, repetitive DNA mapping and genome-size estimation. Conserved characteristics were observed, such as the occurrence of a small number of clusters of rDNAs and U snDNAs, in contrast to the multiple clusters/dispersal of the H3 histone genes. The positions of U2 snDNA and 18S rDNA are also conserved, being intermingled within the largest autosome. The distribution and base-pair composition of the heterochromatin and repetitive DNA pools of these organisms differed, suggesting reorganization. Although the microsatellite arrays had a similar distribution pattern, being dispersed along entire chromosomes, as has been observed in some grasshopper species, a band-like pattern was also observed in the E. surinamensis chromosomes, putatively due to their amplification and clustering. In addition to these differences, the genome of E. surinamensis is approximately 2.5 times larger than that of G. assimilis, which we hypothesize is due to the amplification of repetitive DNAs. Finally, we discuss the possible involvement of repetitive DNAs in the differentiation of the neo-sex chromosomes of E. surinamensis, as has been reported in other eukaryotic groups. This study provided an opportunity to explore the evolutionary dynamics of repetitive DNAs in two non-model species and will contribute to the

  5. Repetitive subcutaneous implantation of different types of (biodegradable) biomaterials alters the foreign body reaction

    NARCIS (Netherlands)

    van Luyn, MJA; Plantinga, JA; Brouwer, LA; Khouw, IMSL; de Leij, LFMH; van Wachem, PB

    2001-01-01

    In the present study two biodegradable materials (cross-linked collagens) and two non-biodegradable materials (polyurethane and silicone) were applied in a repetitive subcutaneous implantation model in rats. In contrast to the first challenge, the second challenge with the same type of material, but

  6. Effects of Vocabulary and Phonotactic Probability on 2-Year-Olds' Nonword Repetition

    Science.gov (United States)

    Verhagen, Josje; de Bree, Elise; Mulder, Hanna; Leseman, Paul

    2017-01-01

    This study investigates the relationship between nonword repetition (NWR) and vocabulary in 2-year-olds. Questions addressed are whether (1) NWR and vocabulary are associated, (2) phonotactic probability affects NWR, and (3) there is an interaction effect between phonotactic probability and vocabulary on NWR performance. The general aim of the…

  7. Art Therapy with Orphaned Children: Dynamics of Early Relational Trauma and Repetition Compulsion

    Science.gov (United States)

    Meshcheryakova, Ksenia

    2012-01-01

    This article explores the dynamics of orphaned children's engagement with art therapy in a group of preadolescent children living in a Russian orphanage. The phenomenon of repetition compulsion (i.e., origins in past traumatic experiences, destructive consequences, and protective psychic function) is discussed with respect to the children's…

  8. Repetitive transcranial magnetic stimulation for levodopa-induced dyskinesias in Parkinson's disease.

    NARCIS (Netherlands)

    Filipovic, S.R.; Rothwell, J.C.; Warrenburg, B.P.C. van de; Bhatia, K.P.

    2009-01-01

    In a placebo-controlled, single-blinded, crossover study, we assessed the effect of "real" repetitive transcranial magnetic stimulation (rTMS) versus "sham" rTMS (placebo) on peak dose dyskinesias in patients with Parkinson's disease (PD). Ten patients with PD and prominent dyskinesias had rTMS (1,8

  9. The effects of subthreshold 1 Hz repetitive TMS on cortico-cortical and interhemispheric coherence

    NARCIS (Netherlands)

    Strens, L.H.; Oliviero, A.; Bloem, B.R.; Gerschlager, W.; Rothwell, J.C.; Brown, P.

    2002-01-01

    OBJECTIVES: Repetitive transcranial magnetic stimulation (rTMS) shows promise as a treatment for various movement and psychiatric disorders. Just how rTMS may have persistent effects on cortical function remains unclear. We hypothesised that it may act by modulating cortico-cortical and interhemisph

  10. Reductions in CI amplitude after repetitive transcranial magnetic stimulation (rTMS) over the striate cortex

    NARCIS (Netherlands)

    Schutter, D.J.L.G.; Honk, E.J. van

    2003-01-01

    Slow repetitive transcranial magnetic stimulation (rTMS) is a method capable of transiently inhibiting cortical excitability and disrupting information processing in the visual system. This method can be used to topographically map the functional contribution of different cortical brain areas in vis

  11. Femtosecond Ti:sapphire cryogenic amplifier with high gain and MHz repetition rate

    DEFF Research Database (Denmark)

    Dantan, Aurelien Romain; Laurat, Julien; Ourjoumtsev, Alexei

    2007-01-01

    We demonstrate high gain amplification of 160-femtosecond pulses in a compact double-pass cryogenic Ti:sapphire amplifier. The setup involves a negative GVD mirrors recompression stage, and operates with a repetition rate between 0.2 and 4 MHz with a continuous pump laser. Amplification factors...

  12. The Perseverative Thinking Questionnaire (PTQ): validation of a content-independent measure of repetitive negative thinking

    NARCIS (Netherlands)

    Ehring, T.; Zetsche, U.; Weidacker, K.; Wahl, K.; Schönfeld, S.; Ehlers, A.

    2011-01-01

    Repetitive negative thinking (RNT) has been found to be involved in the maintenance of several types of emotional problems and has therefore been suggested to be a transdiagnostic process. However, existing measures of RNT typically focus on a particular disorder-specific content. In this article, t

  13. Temporal Dynamics of Repetitions during the Early Stage of Stuttering: An Acoustic Study

    Directory of Open Access Journals (Sweden)

    Tara. V.K

    2011-01-01

    Full Text Available The purpose of this study is to compare the duration characteristic of sound repetitions in the speech of adults who stutter (S=10 recorded near the onset of their stuttering to those of controlled nonstuttering adults (C=10. Dysfluent episodes are identified in digital recordings of the clients read speech. The digitized signals are analyzed by means of Cool Edit Pro software. Using visual displays of sound spectrograms, the durations of the spoken repetition units, the silent intervals between the units and the total dysfluency are measured. The stutterers exhibit shorter silent intervals between spoken repetitions units, which is used as one of the parameter for objective assessment of early stuttering. The total duration of the stutterer’s dysfluency is significantly shorter because of their shorter silent intervals when compared to dysfluency of equal repetition units produced by control subjects. Analysis reveal that silent interval duration is capable of differentiating stuttering from control client with 77.4 - 95 % accuracy. In this work 80% of data are used for training and remaining 20% for testing.

  14. "N"-2 Repetition Costs Depend on Preparation in Trials "n"-1 and "n"-2

    Science.gov (United States)

    Scheil, Juliane; Kleinsorge, Thomas

    2014-01-01

    In task switching, a common result supporting the notion of inhibitory processes as a determinant of switch costs is the occurrence of "n"-2 repetition costs. Evidence suggests that this effect is not affected by preparation. However, the role of preparation on preceding trials has been neglected so far. In this study, evidence for an…

  15. Temporal strategy and performance during a fatiguing short-cycle repetitive task

    NARCIS (Netherlands)

    Bosch, T.; Mathiassen, S.E.; Hallman, D.; Looze, M.P. de; Lyskov, E.; Visser, B.; Dieën, J.H. van

    2012-01-01

    This study investigated temporal changes in movement strategy and performance during fatiguing short-cycle work. Eighteen participants performed six 7-min work blocks with repetitive reaching movements at 0.5 Hz, each followed by a 5.5-min rest break for a total duration of 1 h. Electromyography (EM

  16. Molecular characterization and evolution of an interspersed repetitive DNA family of oysters.

    Science.gov (United States)

    López-Flores, Inmaculada; Ruiz-Rejón, Carmelo; Cross, Ismael; Rebordinos, Laureana; Robles, Francisca; Navajas-Pérez, Rafael; de la Herrán, Roberto

    2010-12-01

    When genomic DNA from the European flat oyster Ostrea edulis L. was digested by BclI enzyme, a band of about 150 bp was observed in agarose gel. After cloning and sequencing this band and analysing their molecular characteristics and genomic organization by means of Southern blot, in situ hybridisation, and polymerase chain reaction (PCR) protocols, we concluded that this band is an interspersed highly repeated DNA element, which is related in sequence to the flanking regions of (CT)-microsatellite loci of the species O. edulis and Crassostrea gigas. Furthermore, we determined that this element forms part of a longer repetitive unit of 268 bp in length that, at least in some loci, is present in more than one copy. By Southern blot hybridisation and PCR amplifications-using primers designed for conserved regions of the 150-bp BclI clones of O. edulis-we determined that this repetitive DNA family is conserved in five other oyster species (O. stentina, C. angulata, C. gigas, C. ariakensis, and C. sikamea) while it is apparently absent in C. gasar. Finally, based on the analysis of the repetitive units in these oyster species, we discuss the slow degree of concerted evolution in this interspersed repetitive DNA family and its use for phylogenetic analysis.

  17. Repetition and Focus on Form in Processing L2 Spanish Words: Implications for Pronunciation Instruction

    Science.gov (United States)

    Trofimovich, Pavel; Gatbonton, Elizabeth

    2006-01-01

    Situated in the context of learning second language (L2) pronunciation, this article discusses from information-processing and pedagogical perspectives the role of repetitive practice with L2 input and of explicit focus on its form-related (phonological) properties. First, we report the results of an auditory word-priming experiment with 60 L2…

  18. Associations among Nonword Repetition and Phonemic and Vocabulary Awareness: Implications for Intervention

    Science.gov (United States)

    Tattersall, Patricia J.; Nelson, Nickola Wolf; Tyler, Ann A.

    2015-01-01

    Prior research has shown possible relations among nonword repetition (NWR), vocabulary, and phonological processing skills in children with and without language impairment. This study was designed to investigate whether relationships would differ for students with primary language impairment (PLI) and typical language (TL) and whether they would…

  19. Repetition Blindness Reveals Differences between the Representations of Manipulable and Nonmanipulable Objects

    Science.gov (United States)

    Harris, Irina M.; Murray, Alexandra M.; Hayward, William G.; O'Callaghan, Claire; Andrews, Sally

    2012-01-01

    We used repetition blindness to investigate the nature of the representations underlying identification of manipulable objects. Observers named objects presented in rapid serial visual presentation streams containing either manipulable or nonmanipulable objects. In half the streams, 1 object was repeated. Overall accuracy was lower when streams…

  20. Repetitive Behaviors in Autism and Obsessive-Compulsive Disorder: New Perspectives from a Network Analysis

    Science.gov (United States)

    Ruzzano, Laura; Borsboom, Denny; Geurts, Hilde M.

    2015-01-01

    The association between autism and obsessive-compulsive disorder (OCD) seems largely dependent upon observed similarities in the repetitive behaviors that manifest in both disorders. The aim of this study was to use a network approach to explore the interactions between these behaviors. We constructed a network based on clinician's…

  1. Too Much of a Good Thing: Prevention of Computer-Related Repetitive Strain Injuries among Children.

    Science.gov (United States)

    Linden, Paul

    1998-01-01

    Examines computer use and repetitive strain injury (RSI) among children and young adults, emphasizing body-awareness training that teaches people to notice and feel body components; understand principles of relaxation, balance, and movement efficiency; and use economical and strain-free ways of accomplishing movements. Outlines elements of safety…

  2. Repetitive Transcranial Magnetic Stimulation for Negative Symptoms of Schizophrenia : Review and Meta-Analysis

    NARCIS (Netherlands)

    Dlabac-de Lange, Jozarni J.; Knegtering, Rikus; Aleman, Andre

    2010-01-01

    Background: Repetitive transcranial magnetic stimulation (rTMS) has been proposed as a treatment for the negative symptoms of schizophrenia. During the past decade, several trials have reported on the efficacy of rTMS treatment; however, the results were inconsistent. Objective: To assess the effica

  3. Therapeutic benefit of repetitive transcranial magnetic stimulation for severe mirror movements A case report

    Institute of Scientific and Technical Information of China (English)

    Han Sun Kim; Sung Ho Jang; Zee-Ihn Lee; Mi Young Lee; Yun Woo Cho; Migyoung Kweon; Su Min Son

    2013-01-01

    Congenital mirror movements retard typical hand functions, but no definite therapeutic modality is available to treat such movements. We report an 8-year-old boy with severe mirror movements of both hands. His mirror movements were assessed using the Woods and Teuber grading scale and his fine motor skills were also evaluated by the Purdue Pegboard Test. A 2-week regimen of repetitive transcranial magnetic stimulation produced markedly diminished mirror movement symptoms and increased the fine motor skills of both hands. Two weeks after the completion of the regimen, mirror movement grades had improved from grade 4 to 1 in both hands and the Purdue Pegboard Test results of the right and left hands also improved from 12 to 14 or 13. These improvements were maintained for 1 month after the 2-week repetitive transcranial magnetic stimulation regimen. After 18 months, the mirror movement grade was maintained and the Purdue Pegboard test score had improved to 15 for the right hand while the left hand score was maintained at 13. This occurred without any additional repetitive transcranial magnetic stimulation or other treatment. These findings suggest that repetitive transcranial magnetic stimulation for this patient had a therapeutic and long-term effect on mirror movements.

  4. Cognitive Set Shifting Deficits and Their Relationship to Repetitive Behaviors in Autism Spectrum Disorder

    Science.gov (United States)

    Miller, Haylie L.; Ragozzino, Michael E.; Cook, Edwin H.; Sweeney, John A.; Mosconi, Matthew W.

    2015-01-01

    The neurocognitive impairments associated with restricted and repetitive behaviors (RRBs) in autism spectrum disorder (ASD) are not yet clear. Prior studies indicate that individuals with ASD show reduced cognitive flexibility, which could reflect difficulty shifting from a previously learned response pattern or a failure to maintain a new…

  5. Restricted and Repetitive Behaviors in Autism Spectrum Disorders: A Review of Research in the Last Decade

    Science.gov (United States)

    Leekam, Susan R.; Prior, Margot R.; Uljarevic, Mirko

    2011-01-01

    Restricted and repetitive behaviors (RRBs) are a core feature of autism spectrum disorders. They constitute a major barrier to learning and social adaptation, but research on their definition, cause, and capacity for change has been relatively neglected. The last decade of research has brought new measurement techniques that have improved the…

  6. Restricted and Repetitive Behaviors in Young Children with Autism Spectrum Disorders

    Science.gov (United States)

    Richler, Jennifer; Bishop, Somer L.; Kleinke, Jennifer R.; Lord, Catherine

    2007-01-01

    Restricted and repetitive behaviors (RRBs) on the Autism Diagnostic Interview- Revised (ADI-R: Lord, Rutter, & Le Couteur (1994) were examined in 165 children with Autism Spectrum Disorders (ASD), 49 children with non-spectrum developmental disorders (DD), and 65 children with typical development (TD) at approximately 2 years of age. A factor…

  7. Age-Related Differences in Restricted Repetitive Behaviors in Autism Spectrum Disorders

    Science.gov (United States)

    Esbensen, Anna J.; Seltzer, Marsha Mailick; Lam, Kristen S. L.; Bodfish, James W.

    2009-01-01

    Restricted repetitive behaviors (RRBs) were examined in a large group of children, adolescents and adults with ASD in order to describe age-related patterns of symptom change and association with specific contextual factors, and to examine if the patterns of change are different for the various types of RRBs. Over 700 individuals with ASD were…

  8. Restricted and Repetitive Behaviors and Psychiatric Symptoms in Youth with Autism Spectrum Disorders

    Science.gov (United States)

    Stratis, Elizabeth A.; Lecavalier, Luc

    2013-01-01

    Children with autism spectrum disorders (ASD) are at high risk for co-occurring psychiatric disorders. Previous research has suggested that restricted and repetitive behaviors (RRB) are associated with symptoms of co-occurring psychiatric disorders in individuals with ASD, but this relationship is not well understood. The current study…

  9. Restricted and Repetitive Behaviors as Predictors of Outcome in Autism Spectrum Disorders

    Science.gov (United States)

    Troyb, Eva; Knoch, Kelley; Herlihy, Lauren; Stevens, Michael C.; Chen, Chi-Ming; Barton, Marianne; Treadwell, Kimberli; Fein, Deborah

    2016-01-01

    Questions have been raised about the significance of restricted and repetitive behaviors (RRBs) in predicting outcomes of children with Autism Spectrum Disorders (ASDs). Previous studies have yielded mixed findings, but some suggest that the presence of RRBs during preschool years is a negative prognostic indicator for later childhood. This study…

  10. Restricted and Repetitive Behaviors in Individuals with a History of ASDs Who Have Achieved Optimal Outcomes

    Science.gov (United States)

    Troyb, Eva; Orinstein, Alyssa; Tyson, Katherine; Eigsti, Inge-Marie; Naigles, Letitia; Fein, Deborah

    2014-01-01

    Studies of autism spectrum disorders (ASDs) suggest that restricted and repetitive behaviors (RRBs) are particularly difficult to remediate. We examined present and past RRBs in 34 individuals who achieved optimal outcomes (OOs; lost their ASD diagnosis), 45 high-functioning individuals with ASD (HFA) and 34 typically developing (TD) peers. The OO…

  11. Sentence Repetition Accuracy in Adults with Developmental Language Impairment: Interactions of Participant Capacities and Sentence Structures

    Science.gov (United States)

    Poll, Gerard H.; Miller, Carol A.; van Hell, Janet G.

    2016-01-01

    Purpose: We asked whether sentence repetition accuracy could be explained by interactions of participant processing limitations with the structures of the sentences. We also tested a prediction of the procedural deficit hypothesis (Ullman & Pierpont, 2005) that adjuncts are more difficult than arguments for individuals with developmental…

  12. Multi-Rate Fractional-Order Repetitive Control of Shunt Active Power Filter

    DEFF Research Database (Denmark)

    Xie, Chuan; Zhao, Xin; Savaghebi, Mehdi

    2017-01-01

    This paper presents a multi-rate fractional-order repetitive control (MRFORC) scheme for three-phase shunt active power filter (APF). The proposed APF control scheme includes an inner proportional-integral (PI) control loop with a sampling rate identical to switching frequency and an external plug-in...

  13. Repetition suppression to faces in the fusiform face area: A personal and dynamic journey.

    Science.gov (United States)

    Henson, Richard N

    2016-07-01

    I review a number of fMRI studies that investigate the effects of repeating faces on responses in the fusiform face area (FFA). These studies show that repetition suppression (RS), as well as repetition enhancement (RE), are sensitive to multiple factors, including pre-existing stimulus representations, cognitive task, lag between repetitions and spatial attention. Parallel EEG studies provide additional constraints on the timing of these repetition effects. Together, the results suggest that RS is not a unitary phenomenon, but likely subsumes multiple mechanisms that operate under different conditions. These mechanisms of course need to relate to single-cell data and known physiological mechanisms; but to make further progress, I believe we need dynamical neural network models that relate these mechanisms to the properties of neural populations that are measured by fMRI and EEG data. One example model is sketched, in which RS reflects an acceleration of neural dynamics, owing to reduced prediction error within a recurrent visual processing hierarchy.

  14. Autism, DRD3 and repetitive and stereotyped behavior, an overview of the current knowledge

    NARCIS (Netherlands)

    Staal, W.G.

    2015-01-01

    The SNP rs167771 of the dopamine-3-receptor gene (DRD3) has been associated with autism spectrum disorder (ASD) in samples from the United Kingdom, The Netherlands and Spain. The DRD3 polymorphisms of rs167771 are significantly associated with a specific type of repetitive and stereotyped behavior,

  15. Effects of Procedural Content and Task Repetition on Accuracy and Fluency in an EFL Context

    Science.gov (United States)

    Patanasorn, Chomraj

    2010-01-01

    Task-supported language teaching can help provide L2 learners communicative practice in EFL contexts. Additionally, it has been suggested that repetition of tasks can help learners develop their accuracy and fluency (Bygate, 2001; Gass, Mackey, Fernandez, & Alvarez-Torres, 1999; Lynch & Maclean, 2000). The purposes of the study were to investigate…

  16. The Effect of Task Repetition on Fluency and Accuracy of EFL Saudi Female Learners' Oral Performance

    Science.gov (United States)

    Gashan, Amani K.; Almohaisen, Fahad M.

    2014-01-01

    This study aimed to examine the effect of task repetition on foreign language output. Twenty eight Saudi female students in the Preparatory Year (PY) at King Saud university, were randomly selected to conduct an oral information-gap task. The participants were asked to perform the task two times with two-week interval between the two performances.…

  17. Engaging Environmental Turbulence : Organizational Determinants for Repetitive, Quick and Adequate Responses

    NARCIS (Netherlands)

    E.J. Waard (Erik)

    2010-01-01

    textabstractIn the academic debate on dealing with environmental turbulence survival or organizational success is being presented as a result of activating dynamic capabilities to repetitively create temporary advantages. A practical question left open in this debate is which organizational determin

  18. Effects of Procedural Content and Task Repetition on Accuracy and Fluency in an EFL Context

    Science.gov (United States)

    Patanasorn, Chomraj

    2010-01-01

    Task-supported language teaching can help provide L2 learners communicative practice in EFL contexts. Additionally, it has been suggested that repetition of tasks can help learners develop their accuracy and fluency (Bygate, 2001; Gass, Mackey, Fernandez, & Alvarez-Torres, 1999; Lynch & Maclean, 2000). The purposes of the study were to investigate…

  19. The Effects of Repetition and L1 Lexicalization on Incidental Vocabulary Acquisition by Iranian EFL Learners

    Science.gov (United States)

    Heidari-Shahreza, Mohammad Ali; Tavakoli, Mansoor

    2016-01-01

    Based on a prior study by Chen and Truscott, the present study investigated the possible effects of repetition (repeated exposure) and L1 lexicalization on the incidental acquisition and retention of 10 English target words by 90 Persian-speaking EFL learners at an Iranian university. Seven aspects of vocabulary knowledge were measured, including…

  20. Measuring Grammatical Development in Bilingual Mandarin-English Speaking Children with a Sentence Repetition Task

    Science.gov (United States)

    Woon, Chai Ping; Yap, Ngee Thai; Lim, Hui Woan; Wong, Bee Eng

    2014-01-01

    Sentence repetition (SR) tasks have been used to measure children's expressive language skills in normal and abnormal language development, and to examine the development of the speaking skills in second language acquisition, as well as to survey the proficiency of bilingual language development. Recently, SR tasks have been recognized as a…

  1. Sentence Repetition in Deaf Children with Specific Language Impairment in British Sign Language

    Science.gov (United States)

    Marshall, Chloë; Mason, Kathryn; Rowley, Katherine; Herman, Rosalind; Atkinson, Joanna; Woll, Bencie; Morgan, Gary

    2015-01-01

    Children with specific language impairment (SLI) perform poorly on sentence repetition tasks across different spoken languages, but until now, this methodology has not been investigated in children who have SLI in a signed language. Users of a natural sign language encode different sentence meanings through their choice of signs and by altering…

  2. Stimulus-Category and Response-Repetition Effects in Task Switching: An Evaluation of Four Explanations

    Science.gov (United States)

    Druey, Michel D.

    2014-01-01

    In many task-switch studies, task sequence and response sequence interact: Response repetitions produce benefits when the task repeats but produce costs when the task switches. Four different theoretical frameworks have been proposed to explain these effects: a reconfiguration-based account, association-learning models, an episodic-retrieval…

  3. Repetition Suppression in the Left Inferior Frontal Gyrus Predicts Tone Learning Performance.

    Science.gov (United States)

    Asaridou, Salomi S; Takashima, Atsuko; Dediu, Dan; Hagoort, Peter; McQueen, James M

    2016-06-01

    Do individuals differ in how efficiently they process non-native sounds? To what extent do these differences relate to individual variability in sound-learning aptitude? We addressed these questions by assessing the sound-learning abilities of Dutch native speakers as they were trained on non-native tone contrasts. We used fMRI repetition suppression to the non-native tones to measure participants' neuronal processing efficiency before and after training. Although all participants improved in tone identification with training, there was large individual variability in learning performance. A repetition suppression effect to tone was found in the bilateral inferior frontal gyri (IFGs) before training. No whole-brain effect was found after training; a region-of-interest analysis, however, showed that, after training, repetition suppression to tone in the left IFG correlated positively with learning. That is, individuals who were better in learning the non-native tones showed larger repetition suppression in this area. Crucially, this was true even before training. These findings add to existing evidence that the left IFG plays an important role in sound learning and indicate that individual differences in learning aptitude stem from differences in the neuronal efficiency with which non-native sounds are processed.

  4. Effect of the pulse repetition rate on fiber-assisted tissue ablation

    Science.gov (United States)

    Kang, Hyun Wook

    2016-07-01

    The effect of the pulse repetition rate on ablation performance was evaluated ex vivo at various fiber sweeping speeds for an effective 532-nm laser prostatectomy. Three pulse repetition rates (7.5, 15, and 30 kHz) at 100 W were delivered to bovine liver tissue at three sweeping speeds (2, 4, and 6 mm/s) to achieve bulky tissue removal. Ablation performance was quantitatively compared in terms of the ablation volume and the coagulation thickness. The lowest pulse repetition rate of 7.5 kHz attained the highest ablation volume (101.5 ± 12.0 mm3) and the thinnest coagulation (0.7 ± 0.1 mm) along with superficial carbonization. The highest pulse repetition rate of 30 kHz was associated with the least tissue removal (65.8 ± 5.0 mm3) and the deepest thermal denaturation (1.1 ± 0.2 mm). Quantitative evaluations of laser parameters can be instrumental in facilitating ablation efficiency and maintaining hemostatic coagulation during treatment of large-sized benign prostate hyperplasia.

  5. The Effect of Task Repetition and Noticing on EFL Learners' Oral Output

    Science.gov (United States)

    Baleghizadeh, Sasan; Derakhshesh, Ali

    2012-01-01

    Teaching grammar is still a topic of heated debate in second/foreign language teaching. One major approach to teaching grammar holds that the learners should receive reactive focus on form in the context of communicative language teaching. The present study is an attempt to examine the effect of task repetition along with reactive focus on form on…

  6. Multi-gigahertz repetition rate ultrafast waveguide lasers mode-locked with graphene saturable absorbers

    Science.gov (United States)

    Obraztsov, P. A.; Okhrimchuk, A. G.; Rybin, M. G.; Obraztsova, E. D.; Garnov, S. V.

    2016-08-01

    We report the development of an approach to build compact waveguide lasers that operate in the stable fundamental mode-locking regime with multigigahertz repetition rates. The approach is based on the use of depressed cladding multi- or single-mode waveguides fabricated directly in the active laser crystal using the femtosecond laser inscription method and a graphene saturable absorber. Using this approach we achieve the stable self-starting mode-locking operation of a diode-pumped waveguide Nd:YAG laser that delivers picosecond pulses at a repetition rate of up to 11.5 GHz with an average power of 12 mW at a central wavelength of 1064 nm. The saturable absorbers are formed through the chemical vapor deposition of single-layer graphene on the output coupler mirror or directly on the end facet of the laser crystal. The stable self-starting mode-locking operation is achieved by controlling the group delay dispersion in the laser cavity with an intracavity interferometer. The method developed for the creation of compact ultrashort pulse laser generators with gigahertz repetition rates can be extended further and applied for the development of compact high-repetition rate lasers that operate at a wide range of IR wavelengths.

  7. Repetitive Transcranial Magnetic Stimulation in Resistant Visual Hallucinations in a Woman With Schizophrenia: A Case Report.

    Science.gov (United States)

    Ghanbari Jolfaei, Atefeh; Naji, Borzooyeh; Nasr Esfehani, Mehdi

    2016-03-01

    A 29-year-old woman with schizophrenia introduced for application of repetitive transcranial magnetic stimulation for refractory visual hallucinations. Following inhibitory rTMS on visual cortex she reported significant reduction in severity and simplification of complexity of hallucinations, which lasted for three months. rTMS can be considered as a possibly potent treatment for visual hallucinations.

  8. Repetitive magnetic stimulation affects the microenvironment of nerve regeneration and evoked potentials after spinal cord injury.

    Science.gov (United States)

    Jiang, Jin-Lan; Guo, Xu-Dong; Zhang, Shu-Quan; Wang, Xin-Gang; Wu, Shi-Feng

    2016-05-01

    Repetitive magnetic stimulation has been shown to alter local blood flow of the brain, excite the corticospinal tract and muscle, and induce motor function recovery. We established a rat model of acute spinal cord injury using the modified Allen's method. After 4 hours of injury, rat models received repetitive magnetic stimulation, with a stimulus intensity of 35% maximum output intensity, 5-Hz frequency, 5 seconds for each sequence, and an interval of 2 minutes. This was repeated for a total of 10 sequences, once a day, 5 days in a week, for 2 consecutive weeks. After repetitive magnetic stimulation, the number of apoptotic cells decreased, matrix metalloproteinase 9/2 gene and protein expression decreased, nestin expression increased, somatosensory and motor-evoked potentials recovered, and motor function recovered in the injured spinal cord. These findings confirm that repetitive magnetic stimulation of the spinal cord improved the microenvironment of neural regeneration, reduced neuronal apoptosis, and induced neuroprotective and repair effects on the injured spinal cord.

  9. Repetitive magnetic stimulation affects the microenvironment of nerve regeneration and evoked potentials after spinal cord injury

    Directory of Open Access Journals (Sweden)

    Jin-lan Jiang

    2016-01-01

    Full Text Available Repetitive magnetic stimulation has been shown to alter local blood flow of the brain, excite the corticospinal tract and muscle, and induce motor function recovery. We established a rat model of acute spinal cord injury using the modified Allen′s method. After 4 hours of injury, rat models received repetitive magnetic stimulation, with a stimulus intensity of 35% maximum output intensity, 5-Hz frequency, 5 seconds for each sequence, and an interval of 2 minutes. This was repeated for a total of 10 sequences, once a day, 5 days in a week, for 2 consecutive weeks. After repetitive magnetic stimulation, the number of apoptotic cells decreased, matrix metalloproteinase 9/2 gene and protein expression decreased, nestin expression increased, somatosensory and motor-evoked potentials recovered, and motor function recovered in the injured spinal cord. These findings confirm that repetitive magnetic stimulation of the spinal cord improved the microenvironment of neural regeneration, reduced neuronal apoptosis, and induced neuroprotective and repair effects on the injured spinal cord.

  10. Repetitive Transcranial Magnetic Stimulation to the Primary Motor Cortex Interferes with Motor Learning by Observing

    Science.gov (United States)

    Brown, Liana E.; Wilson, Elizabeth T.; Gribble, Paul L.

    2009-01-01

    Neural representations of novel motor skills can be acquired through visual observation. We used repetitive transcranial magnetic stimulation (rTMS) to test the idea that this "motor learning by observing" is based on engagement of neural processes for learning in the primary motor cortex (M1). Human subjects who observed another person learning…

  11. Sublexical Processing in Visual Recognition of Chinese Characters: Evidence from Repetition Blindness for Subcharacter Components

    Science.gov (United States)

    Yeh, Su-Ling; Li, Jing-Ling

    2004-01-01

    Repetition blindness (RB) refers to the failure to detect the second occurrence of a repeated item in rapid serial visual presentation (RSVP). In two experiments using RSVP, the ability to report two critical characters was found to be impaired when these two characters were identical (Experiment 1) or similar by sharing one repeated component…

  12. Update on repetitive transcranial magnetic stimulation in obsessive-compulsive disorder: different targets

    NARCIS (Netherlands)

    Blom, R.M.; Figee, M.; Vulink, N.; Denys, D.

    2011-01-01

    Obsessive-compulsive disorder (OCD) is a chronic, disabling disorder. Ten percent of patients remain treatment refractory despite several treatments. For these severe, treatment-refractory patients, repetitive transcranial magnetic stimulation (rTMS) has been suggested as a treatment option. Since

  13. Tibialis anterior stretch reflex in early stance is suppressed by repetitive transcranial magnetic stimulation

    DEFF Research Database (Denmark)

    Zuur, Abraham T; Christensen, Mark Schram; Sinkjær, Thomas

    2009-01-01

    Abstract A rapid plantar flexion perturbation in the early stance phase of walking elicits a large stretch reflex in tibialis anterior (TA). In this study we use repetitive Transcranial Magnetic Stimulation (rTMS) to test if this response is mediated through a transcortical pathway. TA stretch...

  14. Multiple sessions of low-frequency repetitive transcranial magnetic stimulation in focal hand dystonia

    DEFF Research Database (Denmark)

    Kimberley, Teresa Jacobson; Borich, Michael R; Arora, Sanjeev

    2013-01-01

    Purpose: The ability of low-frequency repetitive transcranial magnetic stimulation (rTMS) to enhance intracortical inhibition has motivated its use as a potential therapeutic intervention in focal hand dystonia (FHD). In this preliminary investigation, we assessed the physiologic and behavioral...

  15. Acute Alcohol Effects on Repetition Priming and Word Recognition Memory with Equivalent Memory Cues

    Science.gov (United States)

    Ray, Suchismita; Bates, Marsha E.

    2006-01-01

    Acute alcohol intoxication effects on memory were examined using a recollection-based word recognition memory task and a repetition priming task of memory for the same information without explicit reference to the study context. Memory cues were equivalent across tasks; encoding was manipulated by varying the frequency of occurrence (FOC) of words…

  16. A Case Study of the Reduction of Aberrant, Repetitive Responses of an Adolescent with Autism.

    Science.gov (United States)

    Gunter, Philip L.; And Others

    1993-01-01

    In this case study, music was applied noncontingently and contingently across four settings with an adolescent male with autism, to reduce aberrant, repetitive vocalizations. The intervention was associated with dramatic reductions in the primary aberrant behavior and reductions in two other aberrant behaviors. Task performance was differentially…

  17. Interpreter's Wrist: Repetitive Stress Injury and Carpal Tunnel Syndrome in Sign Language Interpreters.

    Science.gov (United States)

    Stedt, Joe D.

    1992-01-01

    In a survey concerning repetitive stress injury (RSI) and carpal tunnel syndrome, 87 percent of the 40 sign language interpreters reported that they had at some time experienced at least 2 symptoms associated with RSI, and most interpreters knew others with RSI problems. Data indicate that RSI is a severe problem among sign language interpreters.…

  18. Spatial Concept Learning in Preschool Children: Motoric Experiences and Verbal Repetition as Adjuncts to Passive Listening.

    Science.gov (United States)

    And Others; Worthington, R. Kirby

    1980-01-01

    Thirty-two preschool children were matched by age, sex, and pretest scores on spatial concept knowledge. Four groups were (1) instruction (see and hear) only, (2) verbal repetition, (3) fine motor treatment (hand manipulation), and (4) gross motor treatment (body movement). There was no difference in performance between groups given instruction…

  19. Anxiety and Repetitive Behaviours in Autism Spectrum Disorders and Williams Syndrome: A Cross-Syndrome Comparison

    Science.gov (United States)

    Rodgers, Jacqui; Riby, Deborah M.; Janes, Emily; Connolly, Brenda; McConachie, Helen

    2012-01-01

    Children with Autism Spectrum Disorder or Williams syndrome are vulnerable to anxiety. The factors that contribute to this risk remain unclear. This study compared anxiety in autism spectrum disorder and Williams Syndrome and examined the relationship between repetitive behaviours and anxiety. Thirty-four children with autism and twenty children…

  20. New Evidence for the Theory of Chromosome Organization by Repetitive Elements (CORE).

    Science.gov (United States)

    Tang, Shao-Jun

    2017-02-20

    Repetitive DNA elements were proposed to coordinate chromatin folding and interaction in chromosomes by their intrinsic homology-based clustering ability. A recent analysis of the data sets from chromosome-conformation-capture experiments confirms the spatial clustering of DNA repeats of the same family in the nuclear space, and thus provides strong new support for the CORE theory.

  1. Frequency Adaptive Repetitive Control of Grid-Tied Single-Phase PV Inverters

    DEFF Research Database (Denmark)

    Zhou, Keliang; Yang, Yongheng; Blaabjerg, Frede

    2015-01-01

    . This paper thus explores a frequency adaptive repetitive control strategy for grid converters, which employs fractional delay filters in order to adapt to the change of the grid frequency. Case studies with experimental results of a single-phase grid-connected PV inverter system are provided to verify...

  2. Frequency Adaptive Repetitive Control of Grid-Tied Three-Phase PV iInverters

    DEFF Research Database (Denmark)

    Zhou, Keliang; Yang, Yongheng; Blaabjerg, Frede

    2016-01-01

    in the presence of practical time-varying grid frequency. This paper explores frequency adaptive repetitive control strategy for grid-interfaced converters, which employs fractional delay filter to adapt to the change of grid frequency. Case studies with experimental results of three-phase grid-connected...... converter systems are provided to verify the proposed controller....

  3. Sensory dysfunction associated with repetitive strain injuries of tendinitis and focal hand dystonia: a comparative study.

    Science.gov (United States)

    Byl, N; Wilson, F; Merzenich, M; Melnick, M; Scott, P; Oakes, A; McKenzie, A

    1996-04-01

    Repetitive strain injuries are reaching epidemic levels among workers who perform heavy schedules of rapid alternating movements (eg., computer programmers, data entry workers) or repetitive, sustained, coordinated movements (eg., editors, writers, salespeople). The purpose of this study was to determine if patients with repetitive strain injury demonstrated degraded sensory motor performance with their hands. Sixty age-matched adults were recruited, with 15 each assigned to a healthy adult control group, a healthy musician control group, a tendinitis group, or a focal dystonia group. Four sensory motor subtests from the Sensory Integration and Praxis Test were given to the subjects according to a standardized protocol. Using multiple one-factor analyses of variance in the parametric or nonparametric mode followed by post hoc pairwise testing, no significant differences were found between the healthy controls and the musician controls. On the test of kinesthesia, using the left hand, subjects with tendinitis performed significantly worse than controls and subjects with focal dystonia. Compared with controls, subjects with focal dystonia did significantly worse on graphesthesia and manual form perception (part 1 and part 2). Subjects with focal dystonia also did significantly worse than subjects with tendinitis when using the left hand on graphesthesia and manual form perception (part 2). When treating patients with repetitive strain injury, discriminative sensory motor skills must be carefully assessed and may need to be addressed as part of an effective treatment program.

  4. Operation and Thermal Modeling of the ISIS H– Source from 50 to 2 Hz Repetition Rates

    CERN Document Server

    Pereira, H; Lettry, J

    2013-01-01

    CERN’s Linac4 accelerator H− ion source, currently under construction, will operate at a 2 Hz repetition rate, with pulse length of 0.5 ms and a beam current of 80 mA. Its reliability must exceed 99 % with a mandatory 3 month uninterrupted operation period. A Penning ion source is successfully operated at ISIS; at 50 Hz repetition rate it reliably provides 55 mA H− pulses of 0.25 ms duration over 1 month. The discharge plasma ignition is very sensitive to the temperatures of the discharge region, especially of its cathode. The investigation by modeling and measurement of operation parameters suitable for arc ignition and H− production at 2 Hz is of paramount importance and must be understood prior to the implementation of discharge ion sources in the Linac4 accelerator. In its original configuration, the ISIS H− source delivers beam only if the repetition rate is above 12.5 Hz, this paper describes the implementation of a temperature control of the discharge region aiming at lower repetition rate op...

  5. Liking and wanting pleasant odors: different effects of repetitive exposure in men and women

    Directory of Open Access Journals (Sweden)

    Chantal eTriscoli

    2014-05-01

    Full Text Available Odors can enrich the perception of our environment and are commonly used to attract people in marketing situations. However, the perception of an odor changes over repetitions. This study investigated whether repetitive exposition to olfactory stimuli leads to a change in the perceived pleasantness (liking or in the wish to be further exposed to the same olfactory stimulus (wanting, and whether these two mechanisms show gender differences.Three different pleasant odors were each repeatedly presented for 40 times in random order with a mean inter-stimulus interval of 18 s. Eighteen participants rated both liking and wanting for each of the 120 olfactory stimuli. Wanting ratings decreased significantly over repetitions in women and men, with a steeper decrease for men during the initial trials before plateauing. In contrast, liking ratings decreased significantly over repetitions only in men, with a steeper decrease after the initial ratings, but not in women. Additionally, women scored higher in a questionnaire on reward responsiveness than men.We conclude that positive evaluation (liking and the wish to experience more of the same (wanting are different concepts even in the domain of olfaction. The persistence of perceived pleasantness in women may be due to the attribution of a greater subjective value to odors.

  6. Liking and wanting pleasant odors: different effects of repetitive exposure in men and women.

    Science.gov (United States)

    Triscoli, Chantal; Croy, Ilona; Olausson, Håkan; Sailer, Uta

    2014-01-01

    Odors can enrich the perception of our environment and are commonly used to attract people in marketing situations. However, the perception of an odor changes over repetitions. This study investigated whether repetitive exposition to olfactory stimuli leads to a change in the perceived pleasantness ("liking") or in the wish to be further exposed to the same olfactory stimulus ("wanting"), and whether these two mechanisms show gender differences. Three different pleasant odors were each repeatedly presented for 40 times in random order with a mean inter-stimulus interval of 18 s. Eighteen participants rated both "liking" and "wanting" for each of the 120 olfactory stimuli. Wanting ratings decreased significantly over repetitions in women and men, with a steeper decrease for men during the initial trials before plateauing. In contrast, liking ratings decreased significantly over repetitions only in men, with a steeper decrease after the initial ratings, but not in women. Additionally, women scored higher in a questionnaire on reward responsiveness than men. We conclude that positive evaluation (liking) and the wish to experience more of the same (wanting) are different concepts even in the domain of olfaction. The persistence of perceived pleasantness in women may be due to the attribution of a greater subjective value to odors.

  7. Development of a picosecond CO2 laser system for a high-repetition γ-source

    Energy Technology Data Exchange (ETDEWEB)

    Polyanskiy, M.N.; Pogorelsky, I.V.; Yakimenko, V.E.; Platonenko, V.T.

    2009-04-17

    The concept of a high-repetition-rate, high-average power {gamma}-source is based on Compton backscattering from the relativistic electron beam inside a picosecond CO{sub 2} laser cavity. Proof-of-principle experiments combined with computer simulations allow evaluating the promise of this approach for novel applications in science and technology.

  8. High Repetition Rate and Frequency Stabilized Ho:YLF Laser for CO2 Differential Absorption Lidar

    Science.gov (United States)

    Bai, Yingxin; Yu, Jirong; Petros, M.; Petzar, Pau; Trieu, Bo; Lee, Hyung; Singh, U.

    2009-01-01

    High repetition rate operation of an injection seeded Ho:YLF laser has been demonstrated. For 1 kHz operation, the output pulse energy reaches 5.8mJ and the optical-to-optical efficiency is 39% when the pump power is 14.5W.

  9. "N"-2 Repetition Costs Depend on Preparation in Trials "n"-1 and "n"-2

    Science.gov (United States)

    Scheil, Juliane; Kleinsorge, Thomas

    2014-01-01

    In task switching, a common result supporting the notion of inhibitory processes as a determinant of switch costs is the occurrence of "n"-2 repetition costs. Evidence suggests that this effect is not affected by preparation. However, the role of preparation on preceding trials has been neglected so far. In this study, evidence for an…

  10. Assessing Measurement Invariance for Spanish Sentence Repetition and Morphology Elicitation Tasks

    Science.gov (United States)

    Kapantzoglou, Maria; Thompson, Marilyn S.; Gray, Shelley; Restrepo, M. Adelaida

    2016-01-01

    Purpose: The purpose of this study was to evaluate evidence supporting the construct validity of two grammatical tasks (sentence repetition, morphology elicitation) included in the Spanish Screener for Language Impairment in Children (Restrepo, Gorin, & Gray, 2013). We evaluated if the tasks measured the targeted grammatical skills in the same…

  11. When Thinking Impairs Sleep : Trait, Daytime and Nighttime Repetitive Thinking in Insomnia

    NARCIS (Netherlands)

    Lancee, Jaap; Eisma, Maarten C.; van Zanten, Kristopher B.; Topper, Maurice

    2017-01-01

    We performed two studies in individuals with sleep problems to investigate trait, daytime, and nighttime repetitive thinking as risk factors for insomnia. In Study 1, 139 participants completed questionnaires on worry, rumination, insomnia, anxiety, depression, and a sleep diary. Trait rumination an

  12. Non-Word Repetition in Adolescents with Specific Language Impairment (SLI)

    Science.gov (United States)

    Ebbels, Susan H.; Dockrell, Julie E.; van der Lely, Heather K. J.

    2012-01-01

    Background: Non-word repetition (NWR) difficulties are common, but not universal, among children with specific language impairment (SLI). However, older children and adolescents with SLI have rarely been studied. Studies disagree on the relationship between NWR difficulties and difficulties with other areas of language and literacy. There is also…

  13. Classification Accuracy of Nonword Repetition when Used with Preschool-Age Spanish-Speaking Children

    Science.gov (United States)

    Guiberson, Mark; Rodriguez, Barbara L.

    2013-01-01

    Purpose: The purpose of the present study was to (a) describe and compare the nonword repetition (NWR) performance of preschool-age Spanish-speaking children (3- to 5-year-olds) with and without language impairment (LI) across 2 scoring approaches and (b) to contrast the classification accuracy of a Spanish NWR task when item-level and percentage…

  14. When thinking impairs sleep : Trait, daytime and nighttime repetitive thinking in insomnia

    NARCIS (Netherlands)

    Lancee, J.; Eisma, M.C.; van Zanten, K.B.; Topper, M.

    2017-01-01

    We performed two studies in individuals with sleep problems to investigate trait, daytime, and nighttime repetitive thinking as risk factors for insomnia. In Study 1, 139 participants completed questionnaires on worry, rumination, insomnia, anxiety, depression, and a sleep diary. Trait rumination an

  15. Functions of Repetition in Learners' Private Speech in Japanese Language Classrooms

    Science.gov (United States)

    Yoshida, Reiko

    2008-01-01

    Studies investigating repetition in SL/FL learners' private speech have focused mainly on its cognitive and metacognitive functions. In the present study, the classroom observations, video-recordings of lessons, audio-recordings of six learners and two teachers and simulated recall interviews were conducted in Japanese language classes over two…

  16. The Association between Repetitive, Self-Injurious and Aggressive Behavior in Children with Severe Intellectual Disability

    Science.gov (United States)

    Oliver, Chris; Petty, Jane; Ruddick, Loraine; Bacarese-Hamilton, Monique

    2012-01-01

    We evaluated the independent association between adaptive behavior, communication and repetitive or ritualistic behaviors and self-injury, aggression and destructive behavior to identify potential early risk markers for challenging behaviors. Data were collected for 943 children (4-18 years, M = 10.88) with severe intellectual disabilities. Odds…

  17. Excessive Response-Repetition Costs under Task Switching: How Response Inhibition Amplifies Response Conflict

    Science.gov (United States)

    Grzyb, Kai Robin; Hubner, Ronald

    2013-01-01

    The size of response-repetition (RR) costs, which are usually observed on task-switch trials, strongly varies between conditions with univalent and bivalent stimuli. To test whether top-down or bottom-up processes can account for this effect, we assessed in Experiment 1 baselines for univalent and bivalent stimulus conditions (i.e., for stimuli…

  18. Anxiety and Repetitive Behaviours in Autism Spectrum Disorders and Williams Syndrome: A Cross-Syndrome Comparison

    Science.gov (United States)

    Rodgers, Jacqui; Riby, Deborah M.; Janes, Emily; Connolly, Brenda; McConachie, Helen

    2012-01-01

    Children with Autism Spectrum Disorder or Williams syndrome are vulnerable to anxiety. The factors that contribute to this risk remain unclear. This study compared anxiety in autism spectrum disorder and Williams Syndrome and examined the relationship between repetitive behaviours and anxiety. Thirty-four children with autism and twenty children…

  19. The Effect of Event Repetition on the Production of Story Grammar in Children's Event Narratives

    Science.gov (United States)

    Feltis, Brooke B.; Powell, Martine B.; Roberts, Kim P.

    2011-01-01

    Objective: This study examined the effect of event repetition on the amount and nature of story-grammar produced by children when recalling the event. Method: Children aged 4 years (N=50) and 7 years (N=56) participated in either 1 or 6 occurrences of a highly similar event where details varied across the occurrences. Half the children in each age…

  20. Acute Effects of Low-Load/High-Repetition Single-Limb Resistance Training in COPD.

    Science.gov (United States)

    Nyberg, André; Saey, Didier; Martin, Mickaël; Maltais, François

    2016-12-01

    Exercising small muscle groups at a time allows higher muscle specific workloads compared with whole body aerobic exercises in people with chronic obstructive pulmonary disease (COPD). Whether similar effects also occur with partitioning exercise during low load/high-repetition resistance exercises is uncertain.